Investments - Securities with Gross Unrealized Loss Position (Details) $ in Thousands	Sep. 30, 2022 USD ($) item security	Dec. 31, 2021 USD ($) item security
Net Investment Income [Line Items]
Less Than Twelve Months, Gross Unrealized Loss	$ (5,137)	$ (455)
Less Than Twelve Months, Fair Value	44,031	41,250
Twelve Months or Greater, Gross Unrealized Loss	(1,439)
Twelve Months or Greater, Fair Value	12,423
Total, Gross Unrealized Loss	(6,576)	(455)
Total, Fair Value	$ 56,454	$ 41,250
Number of securities in an unrealized loss position \| security	443	358
Unrealized loss position for 12 months or longer \| item	129	129
U.S. Treasuries
Net Investment Income [Line Items]
Less Than Twelve Months, Gross Unrealized Loss	$ (103)	$ (36)
Less Than Twelve Months, Fair Value	2,611	5,007
Twelve Months or Greater, Gross Unrealized Loss	(201)
Twelve Months or Greater, Fair Value	2,256
Total, Gross Unrealized Loss	(304)	(36)
Total, Fair Value	4,867	5,007
Obligations of states, municipalities and political subdivisions
Net Investment Income [Line Items]
Less Than Twelve Months, Gross Unrealized Loss	(902)	(84)
Less Than Twelve Months, Fair Value	6,161	4,292
Twelve Months or Greater, Gross Unrealized Loss	(461)
Twelve Months or Greater, Fair Value	3,200
Total, Gross Unrealized Loss	(1,363)	(84)
Total, Fair Value	9,361	4,292
Corporate Bonds
Net Investment Income [Line Items]
Less Than Twelve Months, Gross Unrealized Loss	(2,461)	(155)
Less Than Twelve Months, Fair Value	18,067	15,446
Twelve Months or Greater, Gross Unrealized Loss	(611)
Twelve Months or Greater, Fair Value	4,389
Total, Gross Unrealized Loss	(3,072)	(155)
Total, Fair Value	22,456	15,446
Residential and commercial mortgage-backed securities
Net Investment Income [Line Items]
Less Than Twelve Months, Gross Unrealized Loss	(1,229)	(139)
Less Than Twelve Months, Fair Value	11,074	9,687
Twelve Months or Greater, Gross Unrealized Loss	(145)
Twelve Months or Greater, Fair Value	2,135
Total, Gross Unrealized Loss	(1,374)	(139)
Total, Fair Value	13,209	9,687
Other loan-backed and structured securities
Net Investment Income [Line Items]
Less Than Twelve Months, Gross Unrealized Loss	(442)	(41)
Less Than Twelve Months, Fair Value	6,118	6,818
Twelve Months or Greater, Gross Unrealized Loss	(21)
Twelve Months or Greater, Fair Value	443
Total, Gross Unrealized Loss	(463)	(41)
Total, Fair Value	$ 6,561	$ 6,818

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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Number of investments in debt securities measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for 12 months or longer, without an allowance for credit loss. Includes beneficial interest in securitized financial asset.

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