Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Millions |
Dec. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Amortized cost of fixed maturities | $ 7,475.7 | $ 7,295.0 |
| Allowance for credit loss, available for sale | 20.1 | 10.7 |
| Cost of equity securities | 287.9 | 197.1 |
| Premium Receivable, Allowance for Credit Loss | 2.0 | 2.9 |
| Allowance for credit losses | $ (20.1) | $ (10.7) |
| Common stock, par value (in dollars per share) | $ 0.10 | $ 0.10 |
| Common stock, shares authorized (in shares) | 100,000,000 | 100,000,000 |
| Common stock, shares outstanding (in shares) | 58,666,644 | 63,840,442 |
| Accrued Expenses and Other Liabilities | $ 762.6 | $ 705.2 |
| Variable Interest Entity, Primary Beneficiary | ||
| Amortized cost of fixed maturities | 41.7 | 1.7 |
| Accrued Expenses and Other Liabilities | 1.5 | 0.5 |
| Consolidated Entity, Excluding VIE | ||
| Amortized cost of fixed maturities | 7,475.7 | 7,295.0 |
| Allowance for credit loss, available for sale | 20.1 | 10.7 |
| Allowance for credit losses | $ (20.1) | $ (10.7) |
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- Definition Amount of expenses incurred but not yet paid nor invoiced, and liabilities classified as other. No definition available.
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- Definition Amortized cost of 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 Face amount or stated value per share of common stock. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition The maximum number of common shares permitted to be issued by an entity's charter and bylaws. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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- Definition Amount 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 Cost of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI). Excludes equity method investment and investment in equity security without readily determinable fair value. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The carrying value as of the balance sheet date of the estimated valuation allowance to reduce gross premiums receivable to net realizable value. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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