Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 90,110	$ 137,556	$ 182,547	$ 243,519
Unrealized gains and losses on debt securities:
Change in unrealized holding gains and losses, net	(87,505)	(308,352)	6,152	(931,262)
Less: Reclassification adjustment for net losses included in net income			433
Amortization of net unrealized loss on securities transferred from available-for-sale to held-to-maturity	10,312	12,539	20,295	13,121
Change in unrealized gains and losses on debt securities	(77,193)	(295,813)	26,880	(918,141)
Unrealized gains and losses on derivative hedges:
Change in unrealized gains and losses on derivative hedges, net	1,848	4,437	321	9,117
Less: Reclassification adjustment for net gains included in net income	(2,660)	(1,090)	(5,221)	(1,941)
Change in unrealized gains and losses on derivative hedges	(812)	3,347	(4,900)	7,176
Other comprehensive (loss) income, before tax	(78,005)	(292,466)	21,980	(910,965)
Income tax benefit (expense)	18,950	70,791	(5,076)	219,848
Other comprehensive (loss) income	(59,055)	(221,675)	16,904	(691,117)
Comprehensive income (loss)	$ 31,055	$ (84,119)	$ 199,451	$ (447,598)