Consolidated Balance Sheets (unaudited) (Parenthetical) - USD ($) $ in Millions |
Sep. 30, 2022 |
Dec. 31, 2021 |
|---|---|---|
| Statement of Financial Position [Abstract] | ||
| Fixed maturity securities available for sale, amortized cost | $ 6,863.6 | $ 6,903.9 |
| Commercial mortgage loans on real estate, allowances for expected credit losses | 1.1 | 1.1 |
| Premiums and accounts receivable, allowances for expected credit losses | 11.5 | 9.4 |
| Reinsurance recoverables, allowances for expected credit losses | 5.7 | 5.0 |
| Other assets, allowances for credit losses | $ 2.0 | $ 2.5 |
| Common stock, par value (in dollars per share) | $ 0.01 | $ 0.01 |
| Common stock, shares authorized (in shares) | 800,000,000 | 800,000,000 |
| Common stock, shares, issued (in shares) | 55,187,797 | 58,050,202 |
| Common stock, shares outstanding (in shares) | 52,891,708 | 55,754,113 |
| Treasury stock, at cost (in shares) | 2,296,089 | 2,296,089 |
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- Definition Other Assets, Allowance For Credit Loss No definition available.
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- Definition Premiums and Accounts Receivable, Allowance For Credit Loss 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 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 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 financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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 common and preferred shares that were previously issued and that were repurchased by the issuing entity and held in treasury on the financial statement date. This stock has no voting rights and receives no dividends. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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