|**Deferred Acquisition Costs  (Tables)**                                                                              | 3 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                        
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|**Deferred Costs [Abstract]**                                                                                         |                                                                                                                                                                                                                                                                                                                                                                                                                                       
|Deferred Policy Acquisition Costs And Asset Reconciliation, Including the Amortized Deferred Policy Acquisition Costs | The table below shows the deferred policy acquisition costs and asset reconciliation.(In millions)Three months ended March 31,20142013Deferred policy acquisition costs asset, beginning of period$565$470Capitalized deferred policy acquisition costs206198Amortized deferred policy acquisition costs(201)(179)Amortized shadow deferred policy acquisition costs(6)2Deferred policy acquisition costs asset, end of period$564$491
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|(In millions)                                                                                                         |                                                                                                                                                                                                                                                                                                                                                                                                                                       
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|Deferred policy acquisition costs asset, beginning of period                                                          |                                                                                                                                                                                                                                                                                                                                                                                                                                       
|Capitalized deferred policy acquisition costs                                                                         |                                                                                                                                                                                                                                                                                                                                                                                                                                       
|Amortized deferred policy acquisition costs                                                                           |                                                                                                                                                                                                                                                                                                                                                                                                                                       
|Amortized shadow deferred policy acquisition costs                                                                    |                                                                                                                                                                                                                                                                                                                                                                                                                                       
|Deferred policy acquisition costs asset, end of period                                                                |                                                                                                                                                                                                                                                                                                                                                                                                                                       
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