| **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)2013 2012 2011Deferred acquisition costs$624 $598 Reserves for unpaid claim and claim adjustment expenses24,015 24,696 Discount deducted from claim and claim adjustment expense reserves above (based on interest rates ranging from 3.0% to 9.7%)1,586 1,850 Unearned premiums3,718 3,610 Net written premiums7,348 6,964 $6,798Net earned premiums7,271 6,881 6,603Net investment income2,240 2,074 1,845Incurred claim and claim adjustment expenses related to current year5,113 5,266 4,901Incurred claim and claim adjustment expenses related to prior years(115) (180) (429)Amortization of deferred acquisition costs1,362 1,274 1,176Paid claim and claim adjustment expenses5,566 5,257 4,499 |

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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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