Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) shares in Thousands, $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Total fixed-maturities available for sale	$ 5,535,532	$ 5,367,729
Trading securities amortized cost	146,446	234,382
Equity securities, fair value cost	162,320	176,229
Reinvested cash collateral held under securities lending agreements	85,777	48,652
Reinsurance recoverables, paid losses	$ 12	$ 51
Common stock, par or stated value per share	$ 0.001	$ 0.001
Common stock, shares authorized	485,000	485,000
Common stock, shares, issued	176,497	194,408
Common stock, shares, outstanding	157,058	175,421
Treasury stock, shares	19,440	18,987