Consolidated Balance Sheets (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Dec. 31, 2024	Dec. 31, 2023
Statement of Financial Position [Abstract]
Fixed-maturities available for sale, amortized cost	$ 5,511,501	$ 5,599,111
Trading securities, amortized cost	89,479	110,484
Equity securities, cost	144,579	92,124
Reinvested cash collateral held under securities lending agreements	125,723	149,364
Reinsurance recoverables, paid losses	$ 444	$ 59
Common stock, par value (in usd per share)	$ 0.001	$ 0.001
Common stock, shares authorized (in shares)	485,000	485,000
Common stock, shares, issued (in shares)	168,350	173,247
Common stock, shares, outstanding (in shares)	147,569	153,179
Treasury stock (in shares)	20,782	20,068