Investments - Schedule of Realized Gains and Losses (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Investments [Abstract]
Fixed maturity securities, gross realized gains	$ 13	$ 1,543	$ 45	$ 1,543
Fixed maturity securities, gross realized losses	(13)	(2,341)	(20)	(2,652)
Fixed maturity securities	0	(798)	25	(1,109)
Bank loan participations, gross realized gains	137	223	229	531
Bank loan participations, gross realized losses	(1,291)	(313)	(3,057)	(1,261)
Changes in fair values of bank loan participations	1,407	(753)	767	(394)
Bank loan participations	253	(843)	(2,061)	(1,124)
Equity securities, gross realized gains	42	423	252	1,547
Equity securities, gross realized losses	(7)	0	(7)	(177)
Changes in fair values of equity securities	(640)	(1,087)	68	3,141
Equity securities	(605)	(664)	313	4,511
Short-term investments and other, gross realized gains	0	0	1	0
Short-term investments and other, gross realized losses	0	0	(1)	0
Short-term investments and other	0	0	0	0
Total	$ (352)	$ (2,305)	$ (1,723)	$ 2,278