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Consolidated Balance Sheets Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands | Sep. 30, 2024 | Dec. 31, 2023
--- | --- | ---
Statement of Financial Position [Abstract] |  |
Fixed maturity securities, amortized cost | $ 23,003,148 | $ 20,915,245
Fixed maturity securities, allowance for credit loss | 6,983 | 36,751
Cumulative effect adjustment resulting from changes in accounting principles | 1,425 | 3,004
Cumulative effect adjustment resulting from changes in accounting principles | 38,071 | 35,110
Reinsurance recoverable, allowance for credit loss | $ 8,332 | $ 8,404
Preferred stock, par value (in dollars per share) | $ 0.10 | $ 0.10
Preferred stock issued (in shares) | 5,000,000 | 5,000,000
Preferred stock outstanding (in shares) | 0 | 0
Common stock, par value (in dollar per share) | $ 0.20 | $ 0.20
Common shares authorized (in shares) |  | 1,250,000,000
Common shares issued (in shares) | 381,189,906 | 384,817,136
Common shares outstanding (in shares) | 381,189,906 | 384,817,136
Treasury stock issued at cost (in shares) | 412,331,903 | 408,704,807

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