| **Summary of Significant Accounting Policies Product Warranty Liability (Details) (USD $)In Millions, except Per Share data, unless otherwise specified**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       | 3 Months Ended | 12 Months Ended |
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| **Accrued Product Warranty And Deferred Warranty Revenue, Standard And Extended Warranty Programs, Roll Forward:**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |           |            |   |   |   |  |   |  |   |  |
| Accrued product warranty and deferred warranty revenue, at beginning of period                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |           |            |   |   | $ 506 |  | $ 492 |  | $ 602 |  |
| Cost accrued and revenues deferred                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |           |            |   |   | 407 |  | 269 |  | 217 |  |
| Acquisitions                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |           |            |   |   | 5 |  | 0 |  | 0 |  |
| Adjustments to pre-existing warranties                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          | 30             | 27              | 25 | 61 | 79 | [1] | 51 | [1] | 114 | [1] |
| Payments and revenues recognized                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |           |            |   |   | (399) |  | (306) |  | (366) |  |
| Warranty adjustment related to legal settlement                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |           |            |   |   | 0 | [2] | 0 | [2] | (75) | [2] |
| Accrued product warranty and deferred warranty revenue, at end of period                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |           |            |   |   | 598 |  | 506 |  | 492 |  |
| Less: Current portion                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |           |            |   |   | (263) |  | (252) |  | (246) |  |
| Noncurrent accrued product warranty and deferred warranty revenue                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                               |           |            |   |   | 335 |  | 254 |  | 246 |  |
| Adjustments to pre-existing warranties, per diluted share                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       | $ 0.39         | $ 0.34          | $ 0.34 | $ 0.86 |   |  |   |  |   |  |
| **Extended Warranty Program:**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |           |            |   |   |   |  |   |  |   |  |
| Extended warranty program deferred revenue                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |           |            |   |   | 257 |  | 167 |  | 139 |  |
| Revenue recognized under extended warranty programs                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |           |            |   |   | $ 53 |  | $ 46 |  | $ 41 |  |
| Minimum [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |           |            |   |   |   |  |   |  |   |  |
| **Extended Warranty Program:**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |           |            |   |   |   |  |   |  |   |  |
| Product warranty period                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |           |            |   |   | 1 year |  |   |  |   |  |
| Maximum [Member]                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                |           |            |   |   |   |  |   |  |   |  |
| **Extended Warranty Program:**                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |           |            |   |   |   |  |   |  |   |  |
| Product warranty period                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |           |            |   |   | 5 years |  |   |  |   |  |
|                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
| [1]Adjustments to pre-existing warranties reflect changes in our estimate of warranty costs for products sold in prior periods. Such adjustments typically occur when claims experience deviates from historic and expected trends. In the third quarter of 2011, we recorded adjustments for changes in estimates of $30 million, or $0.39 per diluted share. In the second quarter of 2011, we recorded adjustments for changes in estimates of $27 million, or $0.34 per diluted share. In the third quarter of 2010, we recorded adjustments for changes in estimates of $25 million, or $0.34 per diluted share. In the second quarter of 2009, we recorded material adjustments for changes in estimates of $61 million or $0.86 per diluted share.[2]See Note 2, Restructurings and impairments, under Ford related restructuring activity for discussion regarding warranty adjustments related to the Ford Settlement. |

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|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.
+ References
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| - Definition
Total liability for standard and extended product warranties acquired in a business acquisition.
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| - Definition
Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers. For classified balance sheets, represents the current portion of the liabilities (due within one year or within the normal operating cycle if longer).
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|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Carrying value as of the balance sheet date of obligations incurred through that date and due after one year (or beyond the operating cycle if longer) for estimated claims under standard and extended warranty protection rights granted to customers.
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| - Definition
Represents the aggregate decrease in the liability related to payments to satisfy claims for standard and extended product warranties.
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| - Definition
Represents the aggregate Increase or Decrease in the liability during the reporting period for accruals related to preexisting standard and extended product warranties (including adjustments for changes in estimates).
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Represents the aggregate increase in the liability for accruals related to standard and extended product warranties issued during the reporting period.
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