| **Investments (Narrative) (Details) (USD $)In Millions, unless otherwise specified**                                                | Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 |
|-------------------------------------------------------------------------------------------------------------------------------------|---------------|---------------|---------------|
| **Gain (Loss) on Investments [Line Items]**                                                                                         |          |          |          |
| Fixed maturities, fair value of hybrid securities                                                                                   | $ 18          | $ 31          |          |
| Investments, deposit with various states                                                                                            | 80            | 85            |          |
| Investments in fair value, deposit with various states                                                                              | 14,192        | 13,164        |          |
| Impaired securities                                                                                                                 | 7             | 13            | 12            |
| Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss, Accumulated in Investments | 5             | 1             |          |
| Fixed Maturities [Member]                                                                                                           |          |          |          |
| **Gain (Loss) on Investments [Line Items]**                                                                                         |          |          |          |
| Available-for-sale Securities, Gross Unrealized Gain, Accumulated in Investments                                                    | 558           | 874           |          |
| Number of securities total unrealized loss in an unrealized loss position for 12 months or more                                     | 40            | 4             | 20            |
| Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss, Accumulated in Investments | 5             | 1             | 5             |
| Equity Securities [Member]                                                                                                          |          |          |          |
| **Gain (Loss) on Investments [Line Items]**                                                                                         |          |          |          |
| Available-for-sale Securities, Gross Unrealized Gain, Accumulated in Investments                                                    | 1,856         | 1,014         |          |
| Number of securities total unrealized loss in an unrealized loss position for 12 months or more                                     |          |          | 2             |
| Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss, Accumulated in Investments | 0             | 0             |          |
| Equity Securities [Member] | Maximum [Member]                                                                                       |          |          |          |
| **Gain (Loss) on Investments [Line Items]**                                                                                         |          |          |          |
| Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss, Accumulated in Investments |          |          | 1             |
| Procter And Gamble Company, Exxon Mobile Corporation And Chevron Corporation [Member]                                               |          |          |          |
| **Gain (Loss) on Investments [Line Items]**                                                                                         |          |          |          |
| Available-for-sale Securities, Gross Unrealized Gain, Accumulated in Investments                                                    | 452           |          |          |
| Three Primary Contributors                                                                                                          |          |          |          |
| **Gain (Loss) on Investments [Line Items]**                                                                                         |          |          |          |
| Number of securities                                                                                                                | 5             |          |          |
| On Deposit With Various States                                                                                                      |          |          |          |
| **Gain (Loss) on Investments [Line Items]**                                                                                         |          |          |          |
| Investments in fair value, deposit with various states                                                                              | $ 84          | $ 93          |          |

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Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss, Accumulated in Investments
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| - Definition
The carrying amount of the asset transferred to a third party to serve as a deposit, which typically serves as security against failure by the transferor to perform under terms of an agreement.
+ References
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| - Definition
Fair value as of the balance sheet date of hybrid instruments.
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.
+ References
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