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Condensed Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
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Statement of Financial Position [Abstract] |  |
Available-for-sale, amortized cost | $ 3,655,954 | $ 3,391,159
Available-for-sale, allowance for credit losses | 899 | 197
Equity securities, cost | 513,255 | 417,897
Premiums and reinsurance balances receivable, allowances for uncollectible amounts | 23,452 | 22,932
Reinsurance balances recoverable on unpaid losses and settlement expenses, allowances for uncollectible amounts | 11,063 | 9,580
Property and equipment, accumulated depreciation | $ 82,340 | $ 76,330
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) | 137,698,263 | 137,598,560
Common stock, shares outstanding (in shares) | 91,837,835 | 91,738,132
Treasury stock, shares (in shares) | 45,860,428 | 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. + References No definition available. + Details
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