Investments- Allowance for Credit Loss Impairments on Fixed Maturity Securities (Details) - Fixed maturity securities - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Debt Securities, Available-for-Sale, Excluding Accrued Interest, Allowance for Credit Loss [Roll Forward] | ||||
| Beginning balance | $ 2.1 | $ 3.1 | $ 2.1 | $ 0.9 |
| Credit losses on fixed maturity securities for which credit losses were not previously reported | 4.0 | 0.2 | 4.0 | 3.3 |
| Net increase (decrease) related to credit losses previously reported | 0.0 | 0.0 | 0.0 | (0.9) |
| Reduction of credit allowances related to sales | 0.0 | (1.2) | 0.0 | (1.2) |
| Write-offs | 0.0 | 0.0 | 0.0 | 0.0 |
| Ending balance | $ 6.1 | $ 2.1 | $ 6.1 | $ 2.1 |
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- Definition Amount excluding accrued interest, of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, excluding accrued interest, of credit loss expense on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) with no credit loss previously recorded. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, excluding accrued interest, of credit loss expense (reversal of expense) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) with previously recorded allowance and not intended to be sold and not more likely than not will be required to sell before recovery of amortized cost basis. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount, excluding accrued interest, of decrease in allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) from sale. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount, excluding accrued interest, of decrease in allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale) from writeoff. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Details
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