| **Postretirement Benefits Fair Value of Pension and Other Post Retirement Benefit Plan Assets by Category (Details) (USD $)In Millions, unless otherwise specified**                                                                                                                                                                                                                                                                                                                                                                                                                                   | Oct. 31, 2011 | Oct. 31, 2010 | Oct. 31, 2009 |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|---------------|
| Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | $ 463         |               | $ 509         |  | $ 473 |
| Totals                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | 462           | [1]           | 508           | [1] |   |
| Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 2,392         |               | 2,479         |  | 2,317 |
| Totals                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | 2,437         | [2]           | 2,542         | [2] |   |
| Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Totals                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | 277           | [1]           | 307           | [1] |   |
| Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Totals                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | 1,237         | [2]           | 1,377         | [2] |   |
| Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Totals                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | 141           | [1]           | 162           | [1] |   |
| Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Totals                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | 1,025         | [2]           | 885           | [2] |   |
| Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Totals                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | 44            | [1]           | 39            | [1] |   |
| Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Totals                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 | 175           | [2]           | 280           | [2] |   |
| Accounts Receivable [Member] | Fair Value, Inputs, Level 3 [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |          |               | 6             |  |   |
| Accounts Receivable [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 1             | [2]           | 1             |  |   |
| Accounts Receivable [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 8             | [2]           | 6             | [2] |   |
| Cash and Cash Equivalents [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 24            |               | 43            |  |   |
| Cash and Cash Equivalents [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 82            |               | 190           |  |   |
| Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 24            |               | 43            |  |   |
| Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 82            |               | 190           |  |   |
| Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Cash and Cash Equivalents [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| US Large Cap [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 100           |               | 93            |  |   |
| US Large Cap [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 492           |               | 482           |  |   |
| US Large Cap [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 100           |               | 93            |  |   |
| US Large Cap [Member] | Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 492           |               | 482           |  |   |
| US Large Cap [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| US Large Cap [Member] | Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| US Large Cap [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| US Large Cap [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| US SMid Cap [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 59            |               | 46            |  |   |
| US SMid Cap [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 242           |               | 193           |  |   |
| US SMid Cap [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 59            |               | 46            |  |   |
| US SMid Cap [Member] | Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 242           |               | 193           |  |   |
| US SMid Cap [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| US SMid Cap [Member] | Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| US SMid Cap [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| US SMid Cap [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Canadian Equity [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 103           |               | 113           |  |   |
| Canadian Equity [Member] | Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 103           |               | 113           |  |   |
| Canadian Equity [Member] | Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Canadian Equity [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| International Equity [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 68            |               | 85            |  |   |
| International Equity [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 179           |               | 202           |  |   |
| International Equity [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 68            |               | 85            |  |   |
| International Equity [Member] | Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 179           |               | 202           |  |   |
| International Equity [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| International Equity [Member] | Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| International Equity [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| International Equity [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Emerging Markets Equity [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 28            |  |   |
| Emerging Markets Equity [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 105           |               | 112           |  |   |
| Emerging Markets Equity [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 28            |  |   |
| Emerging Markets Equity [Member] | Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 105           |               | 112           |  |   |
| Emerging Markets Equity [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Emerging Markets Equity [Member] | Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Emerging Markets Equity [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Emerging Markets Equity [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Common Stock [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 26            |               | 12            |  |   |
| Common Stock [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 50            |  |   |
| Common Stock [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 26            |               | 12            |  |   |
| Common Stock [Member] | Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 50            |  |   |
| Common Stock [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Common Stock [Member] | Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Common Stock [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Common Stock [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Corporate Bond Securities [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 77            |               | 88            |  |   |
| Corporate Bond Securities [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 466           |               | 189           |  |   |
| Corporate Bond Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Corporate Bond Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Corporate Bond Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 77            |               | 88            |  |   |
| Corporate Bond Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 466           |               | 189           |  |   |
| Corporate Bond Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Corporate Bond Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| US Treasury and Government [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 42            |               | 48            |  |   |
| US Treasury and Government [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 225           |               | 309           |  |   |
| US Treasury and Government [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| US Treasury and Government [Member] | Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| US Treasury and Government [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 42            |               | 48            |  |   |
| US Treasury and Government [Member] | Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 225           |               | 309           |  |   |
| US Treasury and Government [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| US Treasury and Government [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Asset-backed Securities [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 4             |               | 6             |  |   |
| Asset-backed Securities [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 19            |               | 24            |  |   |
| Asset-backed Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Asset-backed Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Asset-backed Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 4             |               | 6             |  |   |
| Asset-backed Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 19            |               | 24            |  |   |
| Asset-backed Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Asset-backed Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Collateralized Mortgage Backed Securities [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 1             |               | 4             |  |   |
| Collateralized Mortgage Backed Securities [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 8             |               | 9             |  |   |
| Collateralized Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Collateralized Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Collateralized Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 1             |               | 4             |  |   |
| Collateralized Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 8             |               | 9             |  |   |
| Collateralized Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Collateralized Mortgage Backed Securities [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Common And Preferred Stock [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 231           |               | 284           |  |   |
| Common And Preferred Stock [Member] | Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Common And Preferred Stock [Member] | Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 231           |               | 284           |  |   |
| Common And Preferred Stock [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Commodities Investment [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 17            |               | 16            |  |   |
| Commodities Investment [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 76            |               | 70            |  |   |
| Commodities Investment [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Commodities Investment [Member] | Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Commodities Investment [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 17            |               | 16            |  |   |
| Commodities Investment [Member] | Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 76            |               | 70            |  |   |
| Commodities Investment [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Commodities Investment [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Hedge Funds [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 25            |               | 25            |  |   |
| Hedge Funds [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 99            |               | 102           |  |   |
| Hedge Funds [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Hedge Funds [Member] | Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Hedge Funds [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Hedge Funds [Member] | Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Hedge Funds [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 25            |               | 25            |  | 33 |
| Hedge Funds [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 99            |               | 102           |  | 140 |
| Private Equity Funds [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 19            |               | 14            |  |   |
| Private Equity Funds [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 75            |               | 57            |  |   |
| Private Equity Funds [Member] | Fair Value, Inputs, Level 1 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Private Equity Funds [Member] | Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Private Equity Funds [Member] | Fair Value, Inputs, Level 2 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Private Equity Funds [Member] | Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Private Equity Funds [Member] | Fair Value, Inputs, Level 3 [Member] | Other Postretirement Benefit Plans [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 19            |               | 14            |  | 9 |
| Private Equity Funds [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 75            |               | 57            |  | 35 |
| Mutual Funds [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 34            |               | 32            |  |   |
| Mutual Funds [Member] | Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 34            |               | 32            |  |   |
| Mutual Funds [Member] | Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Mutual Funds [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Real Estate [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 1             |               | 1             |  |   |
| Real Estate [Member] | Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Real Estate [Member] | Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Real Estate [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 1             |               | 1             |  | 1 |
| Unallocated Insurance Contract [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 120           |  |   |
| Unallocated Insurance Contract [Member] | Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Unallocated Insurance Contract [Member] | Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Unallocated Insurance Contract [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 120           |  | 110 |
| Other Plan Assets [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 3             |  |   |
| Other Plan Assets [Member] | Fair Value, Inputs, Level 1 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |     |               | 3             |  |   |
| Other Plan Assets [Member] | Fair Value, Inputs, Level 2 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | 0             |               | 0             |  |   |
| Other Plan Assets [Member] | Fair Value, Inputs, Level 3 [Member] | Pension [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |          |               |          |  |   |
| **Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |          |               |          |  |   |
| Defined Benefit Plan, Fair Value of Plan Assets                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        | $ 0           |               | $ 0           |  |   |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
| [1]For both October 31, 2011 and 2010, the total excludes $1 million of receivables included in the change in plan asset table.[2]For October 31, 2011 and 2010, the total excludes $8 million and $6 million of receivables, respectively, included in the change in plan asset table. In addition, the table above includes the fair value of Canadian pension assets translated at the October 31, 2011 and October 31, 2010 exchange rates while the change in plan asset table includes the fair value of Canadian pension assets translated at historical foreign currency rates. |

| X                                                                                                                                                                                                                                                                                                                    |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Defined Benefit Plan, Fair Value of Plan Assets Excluding Receivables
+ References
No definition available.
+ Details**Name:**nav_DefinedBenefitPlanFairValueOfPlanAssetsExcludingReceivables**Namespace Prefix:**nav_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Assets, usually stocks, bonds, and other investments, that have been segregated and restricted (usually in a trust) to provide benefits, at their fair value as of the measurement date. Plan assets include amounts contributed by the employer (and by employees for a contributory plan) and amounts earned from investing the contributions, less benefits paid. If a plan has liabilities other than for benefits, those non-benefit obligations may be considered as reductions of plan assets.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 35 -Paragraph 50 -URI http://asc.fasb.org/extlink&oid=6867990&loc=d3e12355-114930Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph d(iv)(b)(i) -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 132R -Paragraph 5 -Subparagraph b -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 87 -Paragraph 49 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.  This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6962843&loc=d3e1928-114920
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