Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands |
Sep. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Statement of Financial Position [Abstract] | ||
| Fixed maturity investments trading, amortized cost | $ 25,997,879 | $ 24,658,351 |
| Short-term investments, amortized cost | $ 4,010,180 | $ 4,760,027 |
| Preference shares, par value (in dollars per share) | $ 1.00 | $ 1.00 |
| Preference shares, shares issued (in shares) | 30,000 | 30,000 |
| Preference shares, shares outstanding (in shares) | 30,000 | 30,000 |
| Number Of Authorized Shares Not Disclosed | true | |
| Common shares, par value (in dollars per share) | $ 1.00 | $ 1.00 |
| Common shares, shares issued (in shares) | 40,841,495 | 43,961,539 |
| Common shares, shares outstanding (in shares) | 40,841,495 | 43,961,539 |
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- Definition NumberOfAuthorizedSharesNotDisclosed No definition available.
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- Definition Other Short-Term Investments, Amortized Cost No definition available.
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- Definition Face amount or stated value per share of common stock. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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://www.xbrl.org/2003/role/disclosureRef
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- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Number of shares issued for nonredeemable preferred shares and preferred shares redeemable solely at option of issuer. Includes, but is not limited to, preferred shares issued, repurchased, and held as treasury shares. Excludes preferred shares classified as debt. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Aggregate share number for all nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) held by stockholders. Does not include preferred shares that have been repurchased. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- References No definition available.
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- Definition Amortized cost of investments in debt securities classified as trading. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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