Investments - Disposition of Fixed Income and Equity Securities (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2025	Sep. 30, 2024
Summary of the disposition of fixed income and equity securities
Fixed income securities, available-for-sale	$ 383,181	$ 80,245
Fixed income securities, available-for-sale	343,319	242,955
SALES
Summary of the disposition of fixed income and equity securities
Fixed income securities, available-for-sale	383,956	98,696
Gross Realized Gains - Fixed income securities - available-for-sale	5,076	538
Gross Realized Losses - Fixed income securities - available-for-sale	(3,219)	(2,489)
Net Realized Gain (Loss) - Fixed income securities - available-for-sale	1,857	(1,951)
Proceeds from Sales - Equity securities	87,874	44,863
Gross Realized Gains - Equity securities	46,478	20,276
Gross Realized Losses - Equity securities	(991)	(340)
Net Realized Gain (Loss) - Equity securities	45,487	19,936
Calls And Maturities Of Marketable Securities
Summary of the disposition of fixed income and equity securities
Fixed income securities, available-for-sale	344,629	240,200
Gross Realized Gains - Fixed income securities - available-for-sale	271	89
Gross Realized Losses - Fixed income securities - available-for-sale	(72)	(1,062)
Net Realized Gain (Loss) - Fixed income securities - available-for-sale	$ 199	$ (973)