| **Deferred Acquisition Costs** | 9 Months Ended                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |
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| **Deferred Costs [Abstract]**  |                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |
| Deferred Acquisition Costs     | DEFERRED ACQUISITION COSTS Expenses directly related to successfully acquiring insurance policies – primarily commissions, premium taxes and underwriting costs – are deferred and amortized over the terms of the policies. We update our acquisition cost assumptions periodically to reflect actual experience, and we evaluate the costs for recoverability. The table below shows the deferred policy acquisition costs and asset reconciliation. (In millions) Three months ended September 30, Nine months ended September 30, 2013 2012 2013 2012Deferred policy acquisition costs asset at beginning of period $546 $484 $470 $477Capitalized deferred policy acquisition costs 211 192 612 554Amortized deferred policy acquisition costs (190) (180) (552) (517)Amortized shadow deferred policy acquisition costs 9 (5) 46 (23)Deferred policy acquisition costs asset at end of period $576 $491 $576 $491No premium deficiencies were recorded in the condensed consolidated statements of income, as the sum of the anticipated loss and loss adjustment expenses, policyholder dividends and unamortized deferred acquisition expenses did not exceed the related unearned premiums and anticipated investment income. |

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| - Definition
The entire disclosure for deferred policy acquisition costs.
+ References
Reference 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=6967983&loc=d3e11264-158415Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 30 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6481813&loc=d3e11407-158417
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