|**Accumulated Other Comprehensive Income (Loss) (Tables)**                    | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
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|**Accumulated Other Comprehensive Income (Loss) [Abstract]**                  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                        
|Schedule of accumulated other comprehensive income (loss)                     | Accumulated Other Comprehensive Income (Loss)December 3120112010(In millions)TaxAfter-taxTaxAfter-taxCumulative foreign currency translation adjustment$—$121$—$136Pension and postretirement benefits326(609)220(409)Net unrealized gains (losses) on investments with OTTI losses33(64)39(73)Net unrealized gains (losses) on other investments(533)1,022(348)691Accumulated other comprehensive loss attributable to noncontrolling interests———(19)Accumulated other comprehensive income (loss)$(174)$470$(89)$326
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|December 31                                                                   | 2011                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
|(In millions)                                                                 | Tax                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|Cumulative foreign currency translation adjustment                            | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
|Pension and postretirement benefits                                           | 326                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    
|Net unrealized gains (losses) on investments with OTTI losses                 | 33                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     
|Net unrealized gains (losses) on other investments                            | (533                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                   
|Accumulated other comprehensive loss attributable to noncontrolling interests | —                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      
|Accumulated other comprehensive income (loss)                                 | $                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      

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