Other Comprehensive (Loss) Income (Details) - USD ($) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2023	Mar. 31, 2023	Jun. 30, 2022	Mar. 31, 2022	Jun. 30, 2023	Jun. 30, 2022
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Unrealized gains (losses) on fixed-maturity securities arising during the period, before income taxes	$ (18,236)		$ (69,483)		$ 2,934	$ (149,968)
Income tax (expense) benefit	3,830		14,591		(616)	31,493
Unrealized gains (losses) arising during the period, net of income taxes	(14,406)		(54,892)		2,318	(118,475)
Less reclassification adjustment [Abstract]
Net realized (losses) gains on fixed-maturity securities, before income taxes	(404)		(12)		(1,316)	427
Income tax benefit (expense)	85		2		276	(90)
Reclassification adjustment included in net income	(319)		(10)		(1,040)	337
Change in allowance for credit losses on investments, before income taxes	25		0		(56)	0
Income tax benefit (expense)	(5)		0		12	0
Reclassification adjustment included in net income	20		0		(44)	0
Other comprehensive income (loss)	$ (14,107)	$ 17,509	$ (54,882)	$ (63,930)	$ 3,402	$ (118,812)