Investments - Disposition of Fixed Income and Equity Securities (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Summary of the disposition of fixed income and equity securities
Fixed income securities - available-for-sale	$ 149,939	$ 50,135	$ 53,300
Fixed income securities - available-for-sale	326,297	504,168	1,393,674
Net Realized Gain (Loss) - Fixed income securities - available-for-sale		(2,000)
Net Realized Gain (Loss) - Equity securities	30,792	22,232	20,287
SALES
Summary of the disposition of fixed income and equity securities
Fixed income securities - available-for-sale	150,884	49,960	51,355
Gross Realized Gains - Fixed income securities - available-for-sale	630	451	287
Gross Realized Losses - Fixed income securities - available-for-sale	(4,386)	(2,174)	(2,849)
Net Realized Gain (Loss) - Fixed income securities - available-for-sale	(3,756)	(1,723)	(2,562)
Proceeds from Sales - Equity securities	64,839	51,881	62,212
Gross Realized Gains - Equity securities	31,148	23,482	21,623
Gross Realized Losses - Equity securities	(356)	(1,250)	(1,336)
Net Realized Gain (Loss) - Equity securities	30,792	22,232	20,287
Calls And Maturities Of Marketable Securities
Summary of the disposition of fixed income and equity securities
Fixed income securities - available-for-sale	323,533	506,910	1,393,704
Gross Realized Gains - Fixed income securities - available-for-sale	134	39	196
Gross Realized Losses - Fixed income securities - available-for-sale	(1,400)	(162)	(55)
Net Realized Gain (Loss) - Fixed income securities - available-for-sale	$ (1,266)	$ (123)	$ 141