CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) $ in Millions |
Mar. 31, 2025 |
Dec. 31, 2024 |
|---|---|---|
| Investments | ||
| Amortized Cost of Fixed Maturity Securities | $ 37,860.2 | $ 38,269.9 |
| Debt Securities, Available-for-sale, Allowance for credit losses for Fixed Maturity Securities | 3.8 | 2.8 |
| Financing Receivable, Allowance for Credit Losses, Mortgage Loans | 16.6 | 16.1 |
| Other Assets | ||
| Premium Receivable, Allowance for Credit Loss | 27.0 | 26.8 |
| Reinsurance Recoverable, Allowance for Credit Loss | $ 1.5 | $ 1.5 |
| Stockholders' Equity, Number of Shares, Par Value and Other Disclosure [Abstract] | ||
| Common Stock, Par Value (in dollars per share) | $ 0.10 | $ 0.10 |
| Common Stock, Shares Authorized | 725,000,000 | 725,000,000 |
| Common Stock, Shares Issued | 195,954,270 | 195,460,723 |
| Treasury Stock, Shares at Cost | 20,127,386 | 16,871,752 |
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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 Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury. 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 Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- References No definition available.
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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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- Definition Amount of allowance for credit loss on reinsurance recoverable. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- References No definition available.
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- Definition Number of previously issued common shares repurchased by the issuing entity and held in treasury. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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