Investments - Securities with Gross Unrealized Loss Position (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Net Investment Income [Line Items]
Less than twelve months, gross unrealized loss	$ (4,015)	$ (3,693)
Less than twelve months, fair value	86,979	53,357
Twelve months or greater, gross unrealized loss	(972)	(958)
Twelve months or greater, fair value	9,738	9,955
Gross Unrealized Loss	(4,987)	(4,651)
Fair Value	96,717	63,312
U.S. Treasuries
Net Investment Income [Line Items]
Less than twelve months, gross unrealized loss	(358)	(280)
Less than twelve months, fair value	33,077	12,345
Twelve months or greater, gross unrealized loss	(56)	(50)
Twelve months or greater, fair value	526	515
Gross Unrealized Loss	(414)	(330)
Fair Value	33,603	12,860
Obligations of states, municipalities and political subdivisions
Net Investment Income [Line Items]
Less than twelve months, gross unrealized loss	(839)	(813)
Less than twelve months, fair value	10,400	8,445
Twelve months or greater, gross unrealized loss	(149)	(148)
Twelve months or greater, fair value	1,607	1,639
Gross Unrealized Loss	(988)	(961)
Fair Value	12,007	10,084
Corporate bonds
Net Investment Income [Line Items]
Less than twelve months, gross unrealized loss	(1,859)	(1,698)
Less than twelve months, fair value	27,414	21,104
Twelve months or greater, gross unrealized loss	(354)	(369)
Twelve months or greater, fair value	4,590	4,677
Gross Unrealized Loss	(2,213)	(2,067)
Fair Value	32,004	25,781
Residential and commercial mortgage-backed securities
Net Investment Income [Line Items]
Less than twelve months, gross unrealized loss	(692)	(621)
Less than twelve months, fair value	13,523	8,673
Twelve months or greater, gross unrealized loss	(406)	(383)
Twelve months or greater, fair value	2,964	3,072
Gross Unrealized Loss	(1,098)	(1,004)
Fair Value	16,487	11,745
Other loan-backed and structured securities
Net Investment Income [Line Items]
Less than twelve months, gross unrealized loss	(267)	(281)
Less than twelve months, fair value	2,565	2,790
Twelve months or greater, gross unrealized loss	(7)	(8)
Twelve months or greater, fair value	51	52
Gross Unrealized Loss	(274)	(289)
Fair Value	$ 2,616	$ 2,842

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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