Investments - Disposition of Fixed Income and Equity Securities (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2022	Sep. 30, 2021
Summary of the disposition of fixed income and equity securities
Fixed income securities - available-for-sale	$ 46,448	$ 42,776
Fixed income securities - available-for-sale	176,616	296,561
SALES
Summary of the disposition of fixed income and equity securities
Fixed income securities - available-for-sale	48,559	43,041
Gross Realized Gains - Fixed income securities - available-for-sale	286	1,476
Gross Realized Losses - Fixed income securities - available-for-sale	(2,481)	(107)
Net Realized Gain (Loss) - Fixed income securities - available-for-sale	(2,195)	1,369
Proceeds from Sales - Equity securities	59,264	157,973
Gross Realized Gains - Equity securities	20,410	52,409
Gross Realized Losses - Equity securities	(609)	(1,787)
Net Realized Gain (Loss) - Equity securities	19,801	50,622
Calls And Maturities Of Marketable Securities
Summary of the disposition of fixed income and equity securities
Fixed income securities - available-for-sale	176,991	296,563
Gross Realized Gains - Fixed income securities - available-for-sale	142	471
Gross Realized Losses - Fixed income securities - available-for-sale	(55)	(109)
Net Realized Gain (Loss) - Fixed income securities - available-for-sale	$ 87	$ 362

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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