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Commitments and Contingencies (Narrative) (Details) - USD ($) $ in Millions |  | 12 Months Ended
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Apr. 30, 2022 | Dec. 31, 2022 | Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract] |  |  |
Exposure to earthquake loss | $ 76.7 |  |
Reduction in premiums written, net |  |  | $ 128.0
Additional total refund requested to be provided to private automobile policyholders |  | $ 52.0 |

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- Definition Catastrophe Claims, Maximum Exposure, Carrying Amount + References No definition available. + Details
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- Definition Amount, after premiums ceded to other entities and premiums assumed by the entity, of decrease (increase) in unearned premiums. + References No definition available. + Details
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