| **Other Intangible Assets (Tables)**                         | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
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| **Intangible Assets, Gross (Excluding Goodwill) [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |
| Schedule of Other Intangible Assets                          | Other intangible assets are presented in the following table.   December 31, 2013 December 31, 2012(In millions)Economic Useful Life Gross Carrying Amount Accumulated Amortization Gross Carrying Amount Accumulated AmortizationFinite-lived intangible assets:         Value of business acquired1 - 4 years $64 $63 $62 $43Trade name8 years 8 2 8 —Distribution channel15 years 13 1 13 —Total finite-lived intangible assets  85 66 83 43Indefinite-lived intangible assets:         Syndicate capacity  58   57  Agency force  16   16  Total indefinite-lived intangible assets  74   73  Total other intangible assets  $159 $66 $156 $43 |

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Schedule of Other Intangible Assets [Table Text Block]
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