|**Life Policy And Investment Contract Reserves (Tables)**                                                                 | 12 Months Ended                                                                                                                                                                                                                                                                            
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|**Liability for Future Policy Benefits [Abstract]**                                                                       |                                                                                                                                                                                                                                                                                            
|Reserve In Addition To The Account Balance, Based on Expected No-Lapse Guarantee Benefits And Expected Policy Assessments | This table summarizes our life policy and investment contract reserves:(In millions)At December 31,20132012Ordinary/traditional life$815$752Universal life508483Deferred annuities862850Structured settlements189193Other1617Total life policy and investment contract reserves$2,390$2,295
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|(In millions)                                                                                                             |                                                                                                                                                                                                                                                                                            
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|Ordinary/traditional life                                                                                                 |                                                                                                                                                                                                                                                                                            
|Universal life                                                                                                            |                                                                                                                                                                                                                                                                                            
|Deferred annuities                                                                                                        |                                                                                                                                                                                                                                                                                            
|Structured settlements                                                                                                    |                                                                                                                                                                                                                                                                                            
|Other                                                                                                                     |                                                                                                                                                                                                                                                                                            
|Total life policy and investment contract reserves                                                                        |                                                                                                                                                                                                                                                                                            
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