Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Dec. 31, 2023	Dec. 31, 2022
Statement of Financial Position [Abstract]
Amortized cost on fixed maturities trading investments	$ 4,394,983	$ 4,226,790
Cost - equity security trading investments	654,939	668,843
Cost - short-term investments	179,375	123,928
Reinsurance recoverable, allowance for credit losses	$ (12)	$ 0
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