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v3.25.4

Reinsurance (Narrative) (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2025 | Dec. 31, 2024 | Dec. 31, 2023
Effects Of Reinsurance [Line Items] |  |  |
Property and casualty premiums earned, Ceded | $ 691.6 | $ 659.9 | $ 629.4
Property and casualty losses and LAE, Ceded | 388.2 | 419.1 | 397.3
Reinsurance recoverable on paid and unpaid losses and unearned premiums | 2,011.1 | 1,994.5 |
MCCA [Member] |  |  |
Effects Of Reinsurance [Line Items] |  |  |
Property and casualty premiums earned, Ceded | 29.7 | 39.2 | 32.9
Property and casualty losses and LAE, Ceded | 35.2 | 60.0 | $ 72.8
Reinsurance recoverable on paid and unpaid losses and unearned premiums | $ 829.2 | $ 870.4 |
MCCA [Member] | Reinsurance Receivable [Member] | Reinsurer Concentration Risk [Member] |  |  |
Effects Of Reinsurance [Line Items] |  |  |
Percentage of reinsurance receivable represented by segment | 41.20% |  |

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