CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Statement of Comprehensive Income [Abstract]
Net income, before-tax amount	$ 259,871	$ 213,732
Net income, tax	(57,712)	(42,695)
Net income	202,159	171,037
Before-tax Amount
Net unrealized gains (losses) arising during the period	153,081	(621,482)
Reclassification adjustment for realized (gains) losses included in net income	(1,030)	0
Net change	152,051	(621,482)
Income Tax
Net unrealized gains (losses) arising during the period	(37,260)	147,023
Reclassification adjustment for realized (gains) losses included in net income	251	0
Net change	(37,009)	147,023
Net of Tax Amount
Net unrealized gains (losses) arising during the period	115,821	(474,459)
Reclassification adjustment for realized (gains) losses included in net income	(779)	0
Net change	115,042	(474,459)
Before-tax Amount
Net unrealized gains (losses) arising during the period	10,000	(135,978)
Reclassification adjustment for realized (gains) losses included in net income	39,892	(2,189)
Net change	49,892	(138,167)
Income Tax
Net unrealized gains (losses) arising during the period	(2,434)	32,361
Reclassification adjustment for realized (gains) losses included in net income	(9,710)	521
Net change	(12,144)	32,882
Net of Tax Amount
Net unrealized gains (losses) arising during the period	7,566	(103,617)
Reclassification adjustment for realized (gains) losses included in net income	30,182	(1,668)
Net change	37,748	(105,285)
Total other comprehensive income (loss)	201,943	(759,649)
Total other comprehensive income (loss), income tax	(49,153)	179,905
Total other comprehensive income (loss), net of tax	152,790	(579,744)
Comprehensive income (loss)	$ 354,949	$ (408,707)