|**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.(Dollars in millions)Three months ended March 31,20152014Deferred policy acquisition costs asset, beginning of period$578$565Capitalized deferred policy acquisition costs207206Amortized deferred policy acquisition costs(209)(201)Amortized shadow deferred policy acquisition costs(5)(6)Deferred policy acquisition costs asset, end of period$571$564
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|(Dollars in millions)                                                                                                 | Three months ended March 31,                                                                                                                                                                                                                                                                                                                                                                                                                    
|                                                                                                                      | 2015                                                                                                                                                                                                                                                                                                                                                                                                                                            
|Deferred policy acquisition costs asset, beginning of period                                                          | $                                                                                                                                                                                                                                                                                                                                                                                                                                               
|Capitalized deferred policy acquisition costs                                                                         | 207                                                                                                                                                                                                                                                                                                                                                                                                                                             
|Amortized deferred policy acquisition costs                                                                           | (209                                                                                                                                                                                                                                                                                                                                                                                                                                            
|Amortized shadow deferred policy acquisition costs                                                                    | (5                                                                                                                                                                                                                                                                                                                                                                                                                                              
|Deferred policy acquisition costs asset, end of period                                                                | $                                                                                                                                                                                                                                                                                                                                                                                                                                               
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                    duration X- DefinitionTabular disclosure of the movement in deferred policy acquisition costs.+ ReferencesReference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 30 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=35755530&loc=d3e11264-158415+ Details**Name:**
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