Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Operating Activities
Net income	$ 542,141	$ 757,902	$ 760,467
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for (reversal of) credit losses	189,079	84,553	(106,251)
Depreciation, amortization, and accretion, net	93,458	69,172	113,552
Deferred income tax expense (benefit)	16,837	10,868	45,000
Originations of loans held for sale	(600,671)	(3,352,235)	(3,698,368)
Proceeds from sales of loans held for sale	945,944	3,709,022	3,749,502
Gain on sales of loans held for sale, net	(9,700)	(12,126)	(42,513)
(Increase) decrease in other assets	(290,477)	(187,205)	(34,293)
Increase (decrease) in other liabilities	244,335	82,957	(21,674)
Investment securities (gains) losses, net	76,718	0	799
Share-based compensation expense	32,224	27,904	27,795
Loss on sales of loans	50,064	0	0
Other	(7,329)	677	0
Net cash provided by (used in) operating activities	1,282,623	1,191,489	794,016
Investing Activities
Net cash received (paid) for business combination and divestiture	8,359	0	0
Proceeds from maturities and principal collections of investment securities available for sale	937,967	1,973,990	3,051,158
Proceeds from sales of investment securities available for sale	1,301,520	0	565,400
Purchases of investment securities available for sale	(2,150,430)	(2,287,318)	(6,877,712)
Net proceeds from sales of loans	1,651,154	69,784	111,168
Purchases of loans	(10,623)	(514,475)	(1,624,182)
Net (increase) decrease in loans	(1,524,681)	(3,987,133)	373,964
Net (purchases) redemptions of Federal Reserve Bank stock	(5,081)	15,151	(1,220)
Net (purchases) redemptions of Federal Home Loan Bank stock	128,458	(163,531)	(1,200)
Net (purchases) proceeds from settlement of bank-owned life insurance policies	8,773	9,271	19,045
Net increase in premises, equipment and software	(32,207)	(30,105)	(25,954)
Other	10,757	58,884	25,367
Net cash provided by (used in) investing activities	323,966	(4,855,482)	(4,384,166)
Financing Activities
Net increase (decrease) in deposits	1,858,349	(531,490)	2,735,705
Net increase (decrease) in federal funds purchased and securities sold under repurchase agreements	42,486	(117,545)	36,211
Net increase (decrease) in other short-term borrowings	(599,888)	603,184	(7,520)
Repayments and redemption of long-term debt	(5,404,731)	(700,000)	0
Proceeds from long-term debt, net	3,220,912	3,622,892	0
Dividends paid to common shareholders	(216,061)	(196,148)	(194,677)
Dividends paid to preferred shareholders	(35,950)	(33,163)	(33,163)
Issuances, net of taxes paid, under equity compensation plans	1,940	(2,823)	11,566
Repurchase of common stock	0	(12,987)	(199,932)
Other	0	0	(1,104)
Net cash provided by (used in) financing activities	(1,132,943)	2,631,920	2,347,086
Increase (decrease) in cash and cash equivalents including restricted cash	473,646	(1,032,073)	(1,243,064)
Cash, cash equivalents, and restricted cash at beginning of year	1,977,780	3,009,853	4,252,917
Cash, cash equivalents, and restricted cash at end of year	2,451,426	1,977,780	3,009,853
Supplemental Disclosures:
Income taxes paid	69,753	175,680	204,214
Interest paid	1,112,905	242,040	132,923
Non-cash Activities:
Settlement of acquired debt	$ 31,109	$ 0	$ 0