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Consolidated Balance Sheets (Parentheticals) - USD ($) $ in Thousands | Mar. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Statement of Financial Position [Abstract] |  |
Fixed income securities, held-to-maturity, fair value | $ 19,183 | $ 21,923
Fixed income securities, available-for-sale, allowance for credit loss | 30,381 | 28,212
Fixed income securities, available-for-sale, amortized cost | 7,983,271 | 7,880,697
Commercial mortgage loans, fair value | 197,807 | 178,913
Equity securities, cost | 189,549 | 183,076
Property and equipment, accumulated depreciation and amortization | $ 277,945 | $ 271,409
Preferred stock, par or stated value (in dollars per share) | $ 0 | $ 0
Preferred stock, authorized (in shares) | 5,000,000 | 5,000,000
Preferred stock, issued (in shares) | 8,000 | 8,000
Preferred stock, liquidation preference (in dollars per share) | $ 25,000 | $ 25,000
Common stock, par or stated value (in dollars per share) | $ 2 | $ 2
Common stock, authorized (in shares) | 360,000,000 | 360,000,000
Common stock, issued (in shares) | 105,447,377 | 105,223,307
Treasury stock, common (in shares) | 44,655,938 | 44,586,870

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