| **Transactions With Affiliated Parties**  | 12 Months Ended                                                                                                                                                                                                                                                                          |
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| **Related Party Transactions [Abstract]** |                                                                                                                                                                                                                                                                                     |
| Transactions With Affiliated Parties      | Transactions With Affiliated PartiesWe paid certain officers and directors, or insurance agencies of which they are shareholders, commissions of $7 million in 2016, 2015 and 2014, on premium volume of $44 million, $42 million and $41 million for 2016, 2015 and 2014, respectively. |

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| - References
No definition available.
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| - Definition
The entire disclosure for related party transactions. Examples of related party transactions include transactions between (a) a parent company and its subsidiary; (b) subsidiaries of a common parent; (c) and entity and its principal owners; and (d) affiliates.
+ References
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