Investments - Disposition of Fixed Income and Equity Securities (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025
Summary of the disposition of fixed income and equity securities
Fixed income securities, available-for-sale	$ 126,582	$ 29,970
Fixed income securities, available-for-sale	230,669	241,362
Net Realized Gain (Loss) - Fixed income securities - available-for-sale	(1,000)
SALES
Summary of the disposition of fixed income and equity securities
Fixed income securities, available-for-sale	127,366	29,579
Gross Realized Gains - Fixed income securities - available-for-sale	1,430	188
Gross Realized Losses - Fixed income securities - available-for-sale	(2,445)	(1,000)
Net Realized Gain (Loss) - Fixed income securities - available-for-sale	(1,015)	(812)
Proceeds from Sales - Equity securities	38,426	55,251
Gross Realized Gains - Equity securities	21,494	30,034
Gross Realized Losses - Equity securities	(1,399)	(562)
Net Realized Gain (Loss) - Equity securities	20,095	29,472
Calls And Maturities Of Marketable Securities
Summary of the disposition of fixed income and equity securities
Fixed income securities, available-for-sale	230,684	241,380
Gross Realized Gains - Fixed income securities - available-for-sale	458	62
Gross Realized Losses - Fixed income securities - available-for-sale		(72)
Net Realized Gain (Loss) - Fixed income securities - available-for-sale	$ 458	$ (10)

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