Condensed Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Statement of Comprehensive Income [Abstract]
Net income	$ 141,796	$ 151,903	$ 286,354	$ 304,257
Other comprehensive income (loss), net of tax (Note 15)
Unrealized holding gains (losses) on investments arising during the period for which an allowance for expected losses has not been recognized	20,151	(17,242)	73,772	(51,729)
Less: Reclassification adjustment for net gains (losses) on investments included in net income
Net realized gains (losses) on disposals and non-credit related impairment losses	(1,624)	(2,427)	(3,480)	(5,337)
Net unrealized gains (losses) on investments	21,775	(14,815)	77,252	(46,392)
Other adjustments to comprehensive income (loss), net	0	0	45	(68)
Other comprehensive income (loss), net of tax	21,775	(14,815)	77,297	(46,460)
Comprehensive income (loss)	$ 163,571	$ 137,088	$ 363,651	$ 257,797