| **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 $8 million in 2019, $7 million in 2018 and $7 million in 2017, on premium volume of $48 million, $45 million and $45 million for 2019, 2018 and 2017, 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
Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 850 -URI http://asc.fasb.org/topic&trid=2122745
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