| **Schedule VI. Supplemental Information Concerning Property and Casualty Insurance Operations (Tables)** | 12 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
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| **Supplemental Information for Property, Casualty Insurance Underwriters [Abstract]**                    |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
| Supplemental information concerning property and casualty insurance operations                           | SCHEDULE VI.  SUPPLEMENTAL INFORMATION CONCERNING PROPERTY AND CASUALTY INSURANCE OPERATIONSAs of and for the years ended December 31Consolidated Property and Casualty Operations(In millions)2014 2013 2012Deferred acquisition costs$600 $624  Reserves for unpaid claim and claim adjustment expenses23,271 24,015 Discount deducted from claim and claim adjustment expense reserves above (based on interest rates ranging from 3.5% to 8.0%)1,578 1,586 Unearned premiums3,592 3,718 Net written premiums7,088 7,348 $6,964Net earned premiums7,212 7,271 6,881Net investment income2,031 2,240 2,074Incurred claim and claim adjustment expenses related to current year5,043 5,113 5,266Incurred claim and claim adjustment expenses related to prior years(39) (115) (180)Amortization of deferred acquisition costs1,317 1,362 1,274Paid claim and claim adjustment expenses5,297 5,566 5,257 |

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| - Definition
The tabular disclosure for the supplemental schedule of information for an entity who has a consolidated property-casualty insurance underwriter, unconsolidated property-casualty subsidiary or fifty percent-or-less owned property-casualty equity investee.
+ References
No definition available.
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