Investments - Schedule of Realized Gain (Loss) on Investments (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Investments, Debt and Equity Securities [Abstract]
Sales and other	$ 257,000	$ (66,767,000)	$ (9,716,000)	$ (77,730,000)
Provision for credit losses	0	65,008,000	(16,000)	(7,500,000)
Fair value option—change in fair value	(3,683,000)	868,000	(22,777,000)	7,954,000
Mortgage loans	(1,376,000)	(59,000)	(3,530,000)	(4,918,000)
Other investments	(16,000)	880,000	1,135,000	502,000
Realized gains (losses) from investments	(4,818,000)	(70,000)	(34,904,000)	(81,692,000)
Other gains (losses)	2,626,000	(2,123,000)	8,324,000	2,729,000
Total realized gains (losses)	(2,192,000)	(2,193,000)	(26,580,000)	(78,963,000)
Applicable tax	460,000	461,000	5,582,000	16,583,000
Realized gains (losses), net of tax	(1,732,000)	(1,732,000)	(20,998,000)	(62,380,000)
Exchanges of fixed maturities	3,400,000	21,100,000	$ 82,200,000	$ 39,000,000.0
Exchanges of fixed maturities, net realized gains	$ 0	$ 0