Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Operating Activities
Net income	$ 757,902	$ 760,467	$ 373,695
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for (reversal of) credit losses	84,553	(106,251)	355,022
Depreciation, amortization, and accretion, net	69,172	113,552	69,625
Deferred income tax expense (benefit)	10,868	45,000	(86,192)
Originations of loans held for sale	(3,352,235)	(3,698,368)	(3,466,170)
Proceeds from sales of loans held for sale	3,709,022	3,749,502	2,936,398
Gain on sales of loans held for sale, net	(12,126)	(42,513)	(67,115)
(Increase) decrease in other assets	(187,205)	(34,293)	(375,150)
Increase (decrease) in other liabilities	82,957	(21,674)	281,866
Investment securities (gains) losses, net	0	799	(78,931)
Share-based compensation expense	27,904	27,795	18,641
Other	677	0	55,343
Net cash provided by operating activities	1,191,489	794,016	17,032
Investing Activities
Proceeds from maturities and principal collections of investment securities available for sale	1,973,990	3,051,158	2,291,536
Proceeds from sales of investment securities available for sale	0	565,400	2,649,686
Purchases of investment securities available for sale	(2,287,318)	(6,877,712)	(6,036,179)
Proceeds from sales of loans	69,784	111,168	1,426,954
Purchases of loans	(514,475)	(1,624,182)	(126,152)
Net (increase) decrease in loans	(3,987,133)	373,964	(2,461,302)
Net (purchases) redemptions of Federal Reserve Bank stock	15,151	(1,220)	(658)
Net (purchases) redemptions of Federal Home Loan Bank stock	(163,531)	(1,200)	129,710
Net (purchases) proceeds from settlement of bank-owned life insurance policies	9,271	19,045	(242,300)
Net increase in premises, equipment and software	(30,105)	(25,954)	(30,102)
Other	58,884	25,367	45,834
Net cash used in investing activities	(4,855,482)	(4,384,166)	(2,352,973)
Financing Activities
Net increase (decrease) in deposits	(531,490)	2,735,705	8,284,519
Net increase (decrease) in federal funds purchased and securities sold under repurchase agreements	(117,545)	36,211	62,232
Net increase (decrease) in other short-term borrowings	603,184	(7,520)	(1,745,843)
Repayments and redemption of long-term debt	(700,000)	0	(2,408,939)
Proceeds from long-term debt, net	3,622,892	0	1,445,492
Dividends paid to common shareholders	(196,148)	(194,677)	(189,967)
Dividends paid to preferred shareholders	(33,163)	(33,163)	(33,163)
Issuances, net of taxes paid, under equity compensation plans	(2,823)	11,566	5,407
Repurchase of common stock	(12,987)	(199,932)	(16,246)
Other	0	(1,104)	(1,552)
Net cash provided by financing activities	2,631,920	2,347,086	5,401,940
Increase (decrease) in cash and cash equivalents including restricted cash	(1,032,073)	(1,243,064)	3,065,999
Cash, cash equivalents, and restricted cash at beginning of year	3,009,853	4,252,917	1,186,918
Cash, cash equivalents, and restricted cash at end of year	1,977,780	3,009,853	4,252,917
Supplemental Disclosures:
Income taxes paid	175,680	204,214	110,828
Interest paid	242,040	132,923	319,282
Non-cash Activities:
Loans foreclosed and transferred to other real estate	0	12,408	2,163
Loans transferred to (from) loans held for sale at fair value	(14,480)	(859)	49,821
Premises and equipment transferred to other assets held for sale	$ 24,163	$ 33,379	$ 7,014