|**Other Intangible Assets (Tables)**               | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                   
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|**Schedule of Other Intangible Assets [Abstract]** |                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|Schedule of other intangible assets                | Other intangible assets are presented in the following table.September 30, 2013December 31, 2012(In millions)Gross Carrying AmountAccumulated AmortizationGross Carrying AmountAccumulated AmortizationFinite-lived intangible assets:Value of business acquired$62$62$62$43Trade name818—Distribution channel13113—Total finite-lived intangible assets83648343Indefinite-lived intangible assets7373Total other intangible assets$156$64$156$43
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|                                                   | September 30, 2013                                                                                                                                                                                                                                                                                                                                                                                                                               
|(In millions)                                      | Gross Carrying Amount                                                                                                                                                                                                                                                                                                                                                                                                                            
|Finite-lived intangible assets:                    |                                                                                                                                                                                                                                                                                                                                                                                                                                                  
|Value of business acquired                         | $                                                                                                                                                                                                                                                                                                                                                                                                                                                
|Trade name                                         | 8                                                                                                                                                                                                                                                                                                                                                                                                                                                
|Distribution channel                               | 13                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Total finite-lived intangible assets               | 83                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Indefinite-lived intangible assets                 | 73                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Total other intangible assets                      | $                                                                                                                                                                                                                                                                                                                                                                                                                                                

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