| **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, 2016 2015Property casualty:    Deferred policy acquisition costs asset, beginning of period $388 $379Capitalized deferred policy acquisition costs 210 196Amortized deferred policy acquisition costs (201) (198)Deferred policy acquisition costs asset, end of period $397 $377     Life:    Deferred policy acquisition costs asset, beginning of period $228 $199Capitalized deferred policy acquisition costs 12 11Amortized deferred policy acquisition costs (11) (11)Amortized shadow deferred policy acquisition costs (8) (5)Deferred policy acquisition costs asset, end of period $221 $194     Consolidated:    Deferred policy acquisition costs asset, beginning of period $616 $578Capitalized deferred policy acquisition costs 222 207Amortized deferred policy acquisition costs (212) (209)Amortized shadow deferred policy acquisition costs (8) (5)Deferred policy acquisition costs asset, end of period $618 $571      |

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No definition available.
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| - Definition
Tabular disclosure of the movement in 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=35755530&loc=d3e11264-158415
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