Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands |
Sep. 30, 2026 |
Dec. 31, 2025 |
|---|---|---|
| Statement of Financial Position [Abstract] | ||
| Available-for-sale, amortized cost | $ 3,892,806 | $ 3,642,362 |
| Available-for-sale, allowance for credit losses | 522 | 828 |
| Equity securities, cost | 523,206 | 534,311 |
| Premiums and reinsurance balances receivable, allowances for uncollectible amounts | 21,629 | 23,673 |
| Reinsurance balances recoverable on unpaid losses and settlement expenses, allowances for uncollectible amounts | 10,643 | 11,107 |
| Property and equipment, accumulated depreciation | $ 90,456 | $ 84,459 |
| Common stock, par value (in dollars per share) | $ 0.01 | $ 0.01 |
| Common stock, shares authorized (in shares) | 400,000,000 | 400,000,000 |
| Common stock, shares issued (in shares) | 137,931,006 | 137,739,079 |
| Common stock, shares outstanding (in shares) | 91,732,032 | 91,878,651 |
| Treasury stock, shares (in shares) | 46,198,974 | 45,860,428 |
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- Definition A valuation allowance for the amount deemed uncollectible of an insurance receivable related to a policy by which an insurer indemnifies itself of some or all of the risk associated with another insurance policy. Includes the carrying value as of the balance sheet date of the estimated valuation allowance to reduce gross premiums receivable to net realizable value. No definition available.
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- Definition Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services. 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 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 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 of valuation allowance for reinsurance recoverables for losses reported to the ceding insurer but not yet paid, and for amounts expected based upon statistical projections and other measures of incurred losses and loss settlement expenses which have not yet been reported to the ceding insurer. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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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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