Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
OPERATING ACTIVITIES
Net income	$ 279,101	$ 331,509
Adjustments to reconcile net income to net cash provided by operating activities:
Provision for credit losses	41,227	28,900
Net amortization of premiums and discounts from acquisition	800	1,057
Depreciation and amortization	44,576	39,751
Amortization of debt issuance costs	657	338
Deferred income tax benefit	(11,437)	(6,332)
Net (increase) decrease in trading securities and other earning assets	(6,529)	17,485
Losses (gains) on investment securities, net	4,153	(58,853)
Gains on sales of assets	(4,301)	(3,206)
Amortization of securities premiums, net of discount accretion	32,516	34,617
Originations of loans held for sale	(49,300)	(34,340)
Gains on sales of loans held for sale, net	(1,218)	(910)
Proceeds from sales of loans held for sale	49,672	33,657
Equity-based compensation	12,702	16,741
Changes in:
Accrued income	(19,363)	(22,756)
Accrued expenses and taxes	77,577	(38,518)
Other assets and liabilities, net	(63,208)	285,969
Net cash provided by operating activities	387,625	625,109
Securities held to maturity:
Maturities, calls and principal repayments	336,216	350,282
Purchases	(186,010)	(946,974)
Securities available for sale:
Sales	22,193	0
Maturities, calls and principal repayments	1,005,538	935,626
Purchases	(522,134)	(1,128,812)
Equity securities with readily determinable fair values:
Sales		28,417
Purchases	(194)	(1,019)
Equity securities without readily determinable fair values:
Sales	4,883	13
Maturities, calls and principal repayments	314,881	148
Purchases	(397,752)	(22,529)
Payment on low-income housing tax credit investment commitments	(31,251)	(30,238)
Net increase in loans	(1,859,649)	(2,802,349)
Net decrease in fed funds sold and resell agreements	710,394	499,808
Net cash activity from acquisitions and divestitures	(793)	257,767
Net decrease (increase) in interest-bearing balances due from other financial institutions	38,552	(20,653)
Purchases of premises and equipment	(23,132)	(34,346)
Proceeds from sales of premises and equipment	4,075	6,432
Net cash used in investing activities	(584,183)	(2,908,427)
FINANCING ACTIVITIES
Net decrease in demand and savings deposits	(1,633,496)	(4,038,619)
Net increase in time deposits	2,426,115	18,326
Net decrease in fed funds purchased and repurchase agreements	(464,565)	(924,267)
Proceeds from short-term debt	32,856,000
Repayment of short-term debt	(30,556,000)
Proceeds from long-term debt		110,000
Payment of debt issuance costs		(2,032)
Cash dividends paid	(55,312)	(53,666)
Proceeds from exercise of stock options and sales of treasury shares	1,267	1,336
Purchases of treasury stock	(8,096)	(31,806)
Net cash provided by (used in) financing activities	2,565,913	(4,920,728)
Increase (decrease) in cash and cash equivalents	2,369,355	(7,204,046)
Cash and cash equivalents at beginning of period	1,557,874	9,214,564
Cash and cash equivalents at end of period	3,927,229	2,010,518
Supplemental disclosures:
Income tax payments	67,372	80,053
Total interest payments	577,907	91,564
Noncash disclosures:
Acquisition of low-income housing tax credit investments	56,922	28,409
Commitment to fund low-income housing tax credit investments	$ 56,922	28,409
Transfer of loans to other real estate owned		12,381
Transfer of securities from available-for-sale to held-to-maturity		$ 3,741,208