Investments - Schedule of Gross Unrealized Losses and Fair Value (Details) - USD ($) $ in Thousands	Jun. 30, 2026	Dec. 31, 2025
Total fixed maturity securities, available-for-sale
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, less than 12 months, fair value	$ 507,022	$ 159,643
Fixed maturity securities, less than 12 months, gross unrealized losses	(6,114)	(826)
Fixed maturity securities, 12 months or more, fair value	521,882	621,814
Fixed maturity securities, 12 months or more, gross unrealized losses	(55,423)	(53,229)
Fixed maturity securities, fair value	1,028,904	781,457
Fixed maturity securities, gross unrealized losses	(61,537)	(54,055)
State and municipal
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, less than 12 months, fair value	28,467	26,425
Fixed maturity securities, less than 12 months, gross unrealized losses	(497)	(369)
Fixed maturity securities, 12 months or more, fair value	140,874	152,646
Fixed maturity securities, 12 months or more, gross unrealized losses	(19,249)	(18,684)
Fixed maturity securities, fair value	169,341	179,071
Fixed maturity securities, gross unrealized losses	(19,746)	(19,053)
Residential mortgage-backed
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, less than 12 months, fair value	220,696	63,405
Fixed maturity securities, less than 12 months, gross unrealized losses	(2,622)	(193)
Fixed maturity securities, 12 months or more, fair value	117,064	171,993
Fixed maturity securities, 12 months or more, gross unrealized losses	(14,047)	(13,402)
Fixed maturity securities, fair value	337,760	235,398
Fixed maturity securities, gross unrealized losses	(16,669)	(13,595)
Corporate
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, less than 12 months, fair value	231,849	61,910
Fixed maturity securities, less than 12 months, gross unrealized losses	(2,835)	(243)
Fixed maturity securities, 12 months or more, fair value	193,995	214,235
Fixed maturity securities, 12 months or more, gross unrealized losses	(17,813)	(16,941)
Fixed maturity securities, fair value	425,844	276,145
Fixed maturity securities, gross unrealized losses	(20,648)	(17,184)
Commercial mortgage and asset-backed
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, less than 12 months, fair value	17,071	7,662
Fixed maturity securities, less than 12 months, gross unrealized losses	(64)	(19)
Fixed maturity securities, 12 months or more, fair value	66,064	78,130
Fixed maturity securities, 12 months or more, gross unrealized losses	(4,273)	(4,140)
Fixed maturity securities, fair value	83,135	85,792
Fixed maturity securities, gross unrealized losses	(4,337)	(4,159)
U.S. Treasury securities and obligations guaranteed by the U.S. government
Debt Securities, Available-for-sale [Line Items]
Fixed maturity securities, less than 12 months, fair value	8,939	241
Fixed maturity securities, less than 12 months, gross unrealized losses	(96)	(2)
Fixed maturity securities, 12 months or more, fair value	3,885	4,810
Fixed maturity securities, 12 months or more, gross unrealized losses	(41)	(62)
Fixed maturity securities, fair value	12,824	5,051
Fixed maturity securities, gross unrealized losses	$ (137)	$ (64)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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