Accumulated Other Comprehensive (Loss) Income (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
AOCI Attributable to Parent, Net of Tax
Balance, beginning	$ 2,896,239	$ 2,353,955	$ 3,177,622	$ 2,307,041
Other comprehensive (loss) income before reclassifications			(523,084)	(63,109)
Total other comprehensive loss, net of tax	(167,936)	(12,783)	(522,507)	(65,431)
Balance, ending	2,772,357	2,387,616	2,772,357	2,387,616
(Losses) Gains on Available-For-Sale and Transferred Debt Securities
AOCI Attributable to Parent, Net of Tax
Balance, beginning			27,038	143,443
Other comprehensive (loss) income before reclassifications			(528,317)	(63,468)
Total other comprehensive loss, net of tax			(527,615)	(65,790)
Balance, ending	(500,577)	77,653	(500,577)	77,653
(Losses) Gains on Derivatives Used for Cash Flow Hedges
AOCI Attributable to Parent, Net of Tax
Balance, beginning			321	(353)
Other comprehensive (loss) income before reclassifications			5,233	359
Total other comprehensive loss, net of tax			5,108	359
Balance, ending	5,429	6	5,429	6
Reclassification adjustments for gains and transfers included in net income
AOCI Attributable to Parent, Net of Tax
Reclassification adjustments for gains and transfers included in net income			(708)	(650)
Reclassification adjustments for gains and transfers included in net income, debt securities
AOCI Attributable to Parent, Net of Tax
Reclassification adjustments for gains and transfers included in net income			(583)	(650)
Reclassification adjustments for gains and transfers included in net income, cash flow hedges
AOCI Attributable to Parent, Net of Tax
Reclassification adjustments for gains and transfers included in net income			(125)	0
Reclassification adjustments for amortization included in net income for transferred securities
AOCI Attributable to Parent, Net of Tax
Reclassification adjustments for gains and transfers included in net income			1,285	(1,672)
Accumulated Other Compre- hensive (Loss) Income
AOCI Attributable to Parent, Net of Tax
Balance, beginning	(327,212)	90,442	27,359	143,090
Total other comprehensive loss, net of tax	(167,936)	(12,783)	(522,507)	(65,431)
Balance, ending	$ (495,148)	$ 77,659	$ (495,148)	$ 77,659