Investments - Realized Gain (Loss) on Investments (Details) - USD ($)	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Investments, Debt and Equity Securities [Abstract]
Sales and other	$ (357,000)	$ 4,549,000
Provision for credit losses	(32,767,000)	387,000
Fair value option—change in fair value	1,858,000	(5,338,000)
Other investments	339,000	(6,842,000)
Realized gains (losses) from investments	(30,927,000)	(7,244,000)
Applicable tax	6,495,000	1,521,000
Realized gains (losses), net of tax	(24,432,000)	(5,723,000)
Exchanges of fixed maturities	0	0
Exchanges of fixed maturities, net realized gains	$ 0	$ 0