Investments - Disposition of Fixed Income and Equity Securities (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2023	Mar. 31, 2022
Summary of the disposition of fixed income and equity securities
Fixed income securities - available-for-sale	$ 3,064	$ 10,779
Fixed income securities - available-for-sale	190,303	71,971
SALES
Summary of the disposition of fixed income and equity securities
Fixed income securities - available-for-sale	3,790	8,832
Gross Realized Gains - Fixed income securities - available-for-sale	35	117
Gross Realized Losses - Fixed income securities - available-for-sale	(82)	(31)
Net Realized Gain (Loss) - Fixed income securities - available-for-sale	(47)	86
Proceeds from Sales - Equity securities	3,501	15,726
Gross Realized Gains - Equity securities	2,417	5,901
Gross Realized Losses - Equity securities	(101)
Net Realized Gain (Loss) - Equity securities	2,316	5,901
Calls And Maturities Of Marketable Securities
Summary of the disposition of fixed income and equity securities
Fixed income securities - available-for-sale	190,305	71,974
Gross Realized Gains - Fixed income securities - available-for-sale	35	20
Gross Realized Losses - Fixed income securities - available-for-sale	(40)	(13)
Net Realized Gain (Loss) - Fixed income securities - available-for-sale	$ (5)	$ 7

Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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