Investments - Disposition of Fixed Income and Equity Securities (Details) - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025
Summary of the disposition of fixed income and equity securities
Fixed income securities, available-for-sale	$ 162,043	$ 383,181
Fixed income securities, available-for-sale	352,802	343,319
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	172,041	383,956
Gross Realized Gains - Fixed income securities - available-for-sale	1,483	5,076
Gross Realized Losses - Fixed income securities - available-for-sale	(3,393)	(3,219)
Net Realized Gain (Loss) - Fixed income securities - available-for-sale	(1,910)	1,857
Proceeds from Sales - Equity securities	57,760	87,874
Gross Realized Gains - Equity securities	32,234	46,478
Gross Realized Losses - Equity securities	(2,169)	(991)
Net Realized Gain (Loss) - Equity securities	30,065	45,487
Calls And Maturities Of Marketable Securities
Summary of the disposition of fixed income and equity securities
Fixed income securities, available-for-sale	353,357	344,629
Gross Realized Gains - Fixed income securities - available-for-sale	673	271
Gross Realized Losses - Fixed income securities - available-for-sale	(600)	(72)
Net Realized Gain (Loss) - Fixed income securities - available-for-sale	$ 73	$ 199

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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