CONSOLIDATED BALANCE SHEETS (Parenthetical) - USD ($) shares in Thousands, $ in Thousands |
Jun. 30, 2026 |
Dec. 31, 2025 |
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| Statement of Financial Position [Abstract] | ||
| Fixed maturities, available for sale, amortized cost | $ 13,916,563 | $ 12,937,728 |
| Fixed maturities, available for sale, allowance for credit loss | 1,898 | 1,836 |
| Fixed maturities, held to maturity, fair value | 402,105 | 395,942 |
| Fixed maturities, held to maturity, allowance for expected credit losses | 0 | 0 |
| Equity securities, cost | 606,505 | 581,275 |
| Allowance for expected credit losses | 27,957 | 29,742 |
| Allowance for credit losses on premium balances receivable | 14,479 | 15,821 |
| Allowance for credit losses on reinsurance recoverable for unpaid losses and loss expenses | $ 41,354 | $ 40,340 |
| Common shares, issued (in shares) | 176,580 | 176,580 |
| Common shares, outstanding (in shares) | 73,141 | 74,135 |
| Treasury shares (in shares) | 103,439 | 102,445 |
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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 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 Amortized cost excluding accrued interest, before allowance for credit loss, 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 Amount, excluding accrued interest, of allowance for credit loss on investment in debt security measured at amortized cost (held-to-maturity). Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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 Amount excluding accrued interest, of allowance for credit loss on financing receivable. Excludes net investment in lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Fair value of investment in debt security measured at amortized cost (held-to-maturity). 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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- 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://www.xbrl.org/2003/role/disclosureRef
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