Reserves for Losses and Adjustment Expenses - Reconciliation of Reinsurance Recoverables on Unpaid Losses (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2025 |
Dec. 31, 2024 |
Dec. 31, 2023 |
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| SEC Schedule, 12-17, Insurance Companies, Reinsurance [Line Items] | |||
| Reinsurance recoverable for unpaid claims under retroactive reinsurance, beginning balance | $ 4,172.0 | ||
| Reinsurance recoverable for unpaid claims under retroactive reinsurance, beginning balance, Ending Balance | 4,281.9 | $ 4,172.0 | |
| Provision for losses and LAE for claims incurred | $ (107.6) | $ 35.6 | $ 60.8 |
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, after valuation allowance, recoverable under reinsurance contracts for losses reported to the ceding insurer but not yet paid and amounts expected for incurred losses and settlement expenses, which have not yet been reported to the ceding insurer. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount, after effects of reinsurance, of expense (reversal of expense) for claims incurred in prior reporting periods and related claims settlement costs. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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