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Shareholders' Equity and Other Comprehensive Income (Loss) - Schedule of Changes in Accumulated Other Comprehensive Income (Loss) by Component (Net of Income Taxes) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023	Dec. 31, 2023
Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]
Beginning balance			$ 5,119,993
Other comprehensive income (loss) before reclassifications	$ 233,655	$ (320,770)	32,112	$ (335,573)
Amounts reclassified from AOCI	42,933	36,541	311,175	98,286
Net current period other comprehensive income (loss)	276,588	(284,229)	343,287	(237,287)
Ending balance	5,355,976		5,355,976
Accumulated other comprehensive income (loss), net	(773,786)		(773,786)		$ (1,117,073)
Total
Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]
Beginning balance	(1,050,374)	(1,395,175)	(1,117,073)	(1,442,117)
Net current period other comprehensive income (loss)	276,588	(284,229)	343,287	(237,287)
Ending balance	(773,786)	(1,679,404)	(773,786)	(1,679,404)
Net unamortized holding (losses) gains on AFS investment securities transferred to HTM
Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]
Beginning balance	(521,780)	0	0	0
Other comprehensive income (loss) before reclassifications	0	0	(537,434)	0
Amounts reclassified from AOCI	15,044	0	30,698	0
Net current period other comprehensive income (loss)	15,044	0	(506,736)	0
Ending balance	(506,736)	0	(506,736)	0
Net Unrealized Gains (Losses) on Investment Securities AFS
Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]
Beginning balance	(410,553)	(1,188,087)	(998,259)	(1,220,263)
Other comprehensive income (loss) before reclassifications	193,466	(291,190)	586,495	(258,235)
Amounts reclassified from AOCI	0	0	194,677	(779)
Net current period other comprehensive income (loss)	193,466	(291,190)	781,172	(259,014)
Ending balance	(217,087)	(1,479,277)	(217,087)	(1,479,277)
Accumulated other comprehensive income (loss), net	(10,200)	(13,300)	(10,200)	(13,300)
Net Unrealized Gains (Losses) on Cash Flow Hedges
Changes in Accumulated Other Comprehensive Income (Loss) by Component [Roll Forward]
Beginning balance	(118,041)	(207,088)	(118,814)	(221,854)
Other comprehensive income (loss) before reclassifications	40,189	(29,580)	(16,949)	(77,338)
Amounts reclassified from AOCI	27,889	36,541	85,800	99,065
Net current period other comprehensive income (loss)	68,078	6,961	68,851	21,727
Ending balance	(49,963)	(200,127)	(49,963)	(200,127)
Accumulated other comprehensive income (loss), net	$ (11,600)	$ (12,100)	$ (11,600)	$ (12,100)

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Amount, after tax, of accumulated increase (decrease) in equity from transaction and other event and circumstance from nonowner source.

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