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Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands | Mar. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Statement of Financial Position [Abstract] |  |
Amortized cost on fixed maturities trading investments | $ 4,574,492 | $ 4,394,983
Cost - equity security trading investments | 690,856 | 654,939
Cost - short-term investments | 163,454 | 179,375
Reinsurance recoverable, allowance for credit losses | 0 | (12)
Fixed assets, accumulated depreciation | $ 330,764 | $ 322,729
Common Stock |  |
Common stock, shares authorized (in shares) | 70,000,000 | 70,000,000
Common stock, shares issued (in shares) | 55,371,000 | 55,371,000
Common stock, shares outstanding (in shares) | 55,371,000 | 55,371,000

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