| **Investments (Fair Values And Unrealized Losses By Investment Category And By The Duration Of The Securities' Continuous Unrealized Loss Position) (Details) (USD $)In Millions, unless otherwise specified** | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|---------------|
| **Investments, Unrealized Loss Position [Line Items]**                                                                                                                                                         |          |          |          |
| Less than 12 months Fair Value                                                                                                                                                                                 | $ 1,516       | $ 223         |          |
| Less than 12 months Unrealized Losses                                                                                                                                                                          | 74            | 12            |          |
| 12 months or more Fair Value                                                                                                                                                                                   | 86            | 17            |          |
| 12 months or more Unrealized Losses                                                                                                                                                                            | 5             | 1             |          |
| Total Fair Value                                                                                                                                                                                               | 1,602         | 240           |          |
| Total Unrealized Losses                                                                                                                                                                                        | 79            | 13            |          |
| Fixed Maturities [Member]                                                                                                                                                                                      |          |          |          |
| **Investments, Unrealized Loss Position [Line Items]**                                                                                                                                                         |          |          |          |
| Less than 12 months Fair Value                                                                                                                                                                                 | 1,397         | 112           |          |
| Less than 12 months Unrealized Losses                                                                                                                                                                          | 70            | 2             |          |
| 12 months or more Fair Value                                                                                                                                                                                   | 86            | 17            |          |
| 12 months or more Unrealized Losses                                                                                                                                                                            | 5             | 1             | 5             |
| Total Fair Value                                                                                                                                                                                               | 1,483         | 129           |          |
| Total Unrealized Losses                                                                                                                                                                                        | 75            | 3             |          |
| Fixed Maturities [Member] | States, Municipalities And Political Subdivisions [Member]                                                                                                                         |          |          |          |
| **Investments, Unrealized Loss Position [Line Items]**                                                                                                                                                         |          |          |          |
| Less than 12 months Fair Value                                                                                                                                                                                 | 490           | 53            |          |
| Less than 12 months Unrealized Losses                                                                                                                                                                          | 18            | 1             |          |
| 12 months or more Fair Value                                                                                                                                                                                   | 42            | 0             |          |
| 12 months or more Unrealized Losses                                                                                                                                                                            | 3             | 0             |          |
| Total Fair Value                                                                                                                                                                                               | 532           | 53            |          |
| Total Unrealized Losses                                                                                                                                                                                        | 21            | 1             |          |
| Fixed Maturities [Member] | United States Government [Member]                                                                                                                                                  |          |          |          |
| **Investments, Unrealized Loss Position [Line Items]**                                                                                                                                                         |          |          |          |
| Less than 12 months Fair Value                                                                                                                                                                                 | 1             |          |          |
| Less than 12 months Unrealized Losses                                                                                                                                                                          | 0             |          |          |
| 12 months or more Fair Value                                                                                                                                                                                   | 0             |          |          |
| 12 months or more Unrealized Losses                                                                                                                                                                            | 0             |          |          |
| Total Fair Value                                                                                                                                                                                               | 1             |          |          |
| Total Unrealized Losses                                                                                                                                                                                        | 0             |          |          |
| Fixed Maturities [Member] | Government-Sponsored Enterprises [Member]                                                                                                                                          |          |          |          |
| **Investments, Unrealized Loss Position [Line Items]**                                                                                                                                                         |          |          |          |
| Less than 12 months Fair Value                                                                                                                                                                                 | 199           | 1             |          |
| Less than 12 months Unrealized Losses                                                                                                                                                                          | 27            | 0             |          |
| 12 months or more Fair Value                                                                                                                                                                                   | 1             | 0             |          |
| 12 months or more Unrealized Losses                                                                                                                                                                            | 0             | 0             |          |
| Total Fair Value                                                                                                                                                                                               | 200           | 1             |          |
| Total Unrealized Losses                                                                                                                                                                                        | 27            | 0             |          |
| Fixed Maturities [Member] | Foreign Government [Member]                                                                                                                                                        |          |          |          |
| **Investments, Unrealized Loss Position [Line Items]**                                                                                                                                                         |          |          |          |
| Less than 12 months Fair Value                                                                                                                                                                                 | 10            |          |          |
| Less than 12 months Unrealized Losses                                                                                                                                                                          | 0             |          |          |
| 12 months or more Fair Value                                                                                                                                                                                   | 0             |          |          |
| 12 months or more Unrealized Losses                                                                                                                                                                            | 0             |          |          |
| Total Fair Value                                                                                                                                                                                               | 10            |          |          |
| Total Unrealized Losses                                                                                                                                                                                        | 0             |          |          |
| Fixed Maturities [Member] | Commercial Mortgage Backed Securities [Member]                                                                                                                                     |          |          |          |
| **Investments, Unrealized Loss Position [Line Items]**                                                                                                                                                         |          |          |          |
| Less than 12 months Fair Value                                                                                                                                                                                 | 125           |          |          |
| Less than 12 months Unrealized Losses                                                                                                                                                                          | 5             |          |          |
| 12 months or more Fair Value                                                                                                                                                                                   | 0             |          |          |
| 12 months or more Unrealized Losses                                                                                                                                                                            | 0             |          |          |
| Total Fair Value                                                                                                                                                                                               | 125           |          |          |
| Total Unrealized Losses                                                                                                                                                                                        | 5             |          |          |
| Fixed Maturities [Member] | Corporate Securities [Member]                                                                                                                                                      |          |          |          |
| **Investments, Unrealized Loss Position [Line Items]**                                                                                                                                                         |          |          |          |
| Less than 12 months Fair Value                                                                                                                                                                                 | 572           | 58            |          |
| Less than 12 months Unrealized Losses                                                                                                                                                                          | 20            | 1             |          |
| 12 months or more Fair Value                                                                                                                                                                                   | 43            | 17            |          |
| 12 months or more Unrealized Losses                                                                                                                                                                            | 2             | 1             |          |
| Total Fair Value                                                                                                                                                                                               | 615           | 75            |          |
| Total Unrealized Losses                                                                                                                                                                                        | 22            | 2             |          |
| Equity Securities [Member]                                                                                                                                                                                     |          |          |          |
| **Investments, Unrealized Loss Position [Line Items]**                                                                                                                                                         |          |          |          |
| Less than 12 months Fair Value                                                                                                                                                                                 | 119           | 111           |          |
| Less than 12 months Unrealized Losses                                                                                                                                                                          | 4             | 10            |          |
| 12 months or more Fair Value                                                                                                                                                                                   | 0             | 0             |          |
| 12 months or more Unrealized Losses                                                                                                                                                                            | 0             | 0             |          |
| Total Fair Value                                                                                                                                                                                               | 119           | 111           |          |
| Total Unrealized Losses                                                                                                                                                                                        | 4             | 10            |          |
| Equity Securities [Member] | Common Stock [Member]                                                                                                                                                             |          |          |          |
| **Investments, Unrealized Loss Position [Line Items]**                                                                                                                                                         |          |          |          |
| Less than 12 months Fair Value                                                                                                                                                                                 | 77            | 107           |          |
| Less than 12 months Unrealized Losses                                                                                                                                                                          | 1             | 9             |          |
| 12 months or more Fair Value                                                                                                                                                                                   | 0             | 0             |          |
| 12 months or more Unrealized Losses                                                                                                                                                                            | 0             | 0             |          |
| Total Fair Value                                                                                                                                                                                               | 77            | 107           |          |
| Total Unrealized Losses                                                                                                                                                                                        | 1             | 9             |          |
| Equity Securities [Member] | Preferred Stock [Member]                                                                                                                                                          |          |          |          |
| **Investments, Unrealized Loss Position [Line Items]**                                                                                                                                                         |          |          |          |
| Less than 12 months Fair Value                                                                                                                                                                                 | 42            | 4             |          |
| Less than 12 months Unrealized Losses                                                                                                                                                                          | 3             | 1             |          |
| 12 months or more Fair Value                                                                                                                                                                                   | 0             | 0             |          |
| 12 months or more Unrealized Losses                                                                                                                                                                            | 0             | 0             |          |
| Total Fair Value                                                                                                                                                                                               | 42            | 4             |          |
| Total Unrealized Losses                                                                                                                                                                                        | $ 3           | $ 1           |          |

| X                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss, Accumulated in Investments
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                    |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Available-for-sale Securities, Continuous Unrealized Loss Position, Aggregate Loss, Accumulated in Investments
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Available-for-sale Securities, Continuous Unrealized Loss Position, Less than 12 Months, Aggregate Loss Accumulated In Investments
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This item represents the aggregate fair value of investments in debt and equity securities in an unrealized loss position which are categorized neither as held-to-maturity nor trading securities.
+ References
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|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for less than twelve months.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
This item represents the aggregate fair value of investments in debt and equity securities categorized neither as held-to-maturity nor trading securities that have been in a continuous unrealized loss position for twelve months or longer.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27337-111563Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=27724398&loc=d3e27290-111563
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