Fair Value - Level 3 Assets (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Roll forward of level 3 fair value measurements on a recurring basis
Fair value, asset, recurring basis, unobservable input reconciliation, asset, gain (loss), statement of other comprehensive income or comprehensive income	Other comprehensive income (loss)	Other comprehensive income (loss)
Fair value, asset, recurring basis, unobservable input reconciliation, gain (loss), statement of income or comprehensive income	Net investment income	Net investment income
Level 3
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	$ 24,368	$ 22,559
Included in earnings	(983)	(732)
Included in other comprehensive income (loss)	766	721
Purchases	12,553	10,349
Sales	(3,516)	(2,277)
Transfers into Level 3	39,272	14,408
Transfers out of Level 3	(35,129)	(20,660)
Ending balance	37,331	24,368
Available-for-sale securities | Level 3
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	17,034	18,780
Included in earnings	(1,653)	(779)
Included in other comprehensive income (loss)	766	721
Purchases	10,534	6,891
Sales	(3,432)	(2,277)
Transfers into Level 3	38,719	12,551
Transfers out of Level 3	(31,611)	(18,853)
Ending balance	30,357	17,034
Available-for-sale securities | Level 3 | Corporate debt securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	4,506	3,686
Included in earnings	(129)	4
Included in other comprehensive income (loss)	126	314
Purchases	6,708	4,316
Sales	(1,821)	(1,536)
Transfers into Level 3	8,379	5,611
Transfers out of Level 3	(11,501)	(7,889)
Ending balance	6,268	4,506
Available-for-sale securities | Level 3 | Commercial mortgage-backed securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	10,994	10,910
Included in earnings	(1,519)	(778)
Included in other comprehensive income (loss)	664	311
Purchases	3,826	2,575
Sales	(1,571)	(621)
Transfers into Level 3	30,340	5,373
Transfers out of Level 3	(18,645)	(6,776)
Ending balance	24,089	10,994
Available-for-sale securities | Level 3 | Residential mortgage-backed securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	1,534	4,184
Included in earnings	(5)	(5)
Included in other comprehensive income (loss)	(24)	96
Purchases	0	0
Sales	(40)	(120)
Transfers into Level 3	0	1,567
Transfers out of Level 3	(1,465)	(4,188)
Ending balance	0	1,534
Equity securities | Level 3 | Equity securities
Roll forward of level 3 fair value measurements on a recurring basis
Beginning balance	7,334	3,779
Included in earnings	670	47
Included in other comprehensive income (loss)	0	0
Purchases	2,019	3,458
Sales	(84)	0
Transfers into Level 3	553	1,857
Transfers out of Level 3	(3,518)	(1,807)
Ending balance	$ 6,974	$ 7,334