Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022
Cash flows from operating activities:
Net income	$ 387,517	$ 352,547
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	44,365	48,765
Provision for credit losses	104,189	34,713
Deferred income taxes	72,680	123,905
Gains on sale of securities, net	(45)	(30)
Share-based compensation expense	28,484	28,311
Accretion of discount related to acquired loans	(16,931)	(29,061)
Losses on disposal of premises and equipment	27	3,483
Gains on sale of bank properties held for sale and repossessed real estate	(1,454)	(787)
Net amortization of premiums on investment securities	15,181	21,528
Bank properties held for sale and repossessed real estate write downs	1,525	226
Fair value adjustment for loans held for sale	508	7,604
Originations and purchases of loans held for sale	(666,880)	(1,273,659)
Proceeds from sales of loans held for sale	670,223	1,421,238
(Gains) losses on sales of loans held for sale	(2,327)	2,062
Increase in cash surrender value of BOLI	(18,573)	(17,188)
Net change in:
Accrued interest receivable	(16,665)	(22,788)
Prepaid assets	(4,178)	(1,180)
Operating leases	231	245
Bank owned life insurance	(1,589)	(423)
Trading securities	(82,891)	25,749
Derivative assets	(1,329)	205,641
Miscellaneous other assets	(41,921)	(6,642)
Accrued interest payable	38,945	2,745
Accrued income taxes	(31,740)	(54,219)
Derivative liabilities	217,735	790,388
Miscellaneous other liabilities	125,989	(86,653)
Net cash provided by operating activities	821,076	1,576,520
Cash flows from investing activities:
Proceeds from sales of investment securities available for sale	125,298	482,028
Proceeds from maturities and calls of investment securities held to maturity	145,751	176,401
Proceeds from maturities and calls of investment securities available for sale	404,718	460,910
Proceeds from sales and redemptions of other investment securities	185,875	13,216
Purchases of investment securities available for sale	(34,505)	(1,366,327)
Purchases of investment securities held to maturity		(1,099,691)
Purchases of other investment securities	(193,310)	(20,387)
Net increase in loans	(1,855,352)	(2,516,308)
Net cash received from acquisitions		250,115
Recoveries of loans previously charged off	12,630	15,381
Purchase of bank owned life insurance	(5,966)	(85,966)
Purchases of premises and equipment	(26,372)	(13,781)
Proceeds from redemption and payout of bank owned life insurance policies	5,956	1,188
Proceeds from sale of bank properties held for sale and repossessed real estate	8,392	8,564
Proceeds from sale of premises and equipment	850	3,772
Net cash used in investing activities	(1,226,035)	(3,690,885)
Cash flows from financing activities:
Net increase (decrease) in deposits	585,786	(1,221,468)
Net decrease in federal funds purchased and securities sold under agreements to repurchase and other short-term borrowings	(43,113)	(223,437)
Proceeds from FHLB borrowings	5,350,200
Repayment of FHLB borrowings	(5,350,200)	(13,000)
Common stock issuance	1,356	1,444
Common stock repurchases	(7,409)	(119,261)
Dividends paid	(116,479)	(108,791)
Stock options exercised	1,392	1,516
Net cash provided by (used in) financing activities	421,533	(1,682,997)
Net increase (decrease) in cash and cash equivalents	16,574	(3,797,362)
Cash and cash equivalents at beginning of period	1,312,563	6,721,571
Cash and cash equivalents at end of period	1,329,137	2,924,209
Cash paid for:
Interest	291,649	34,227
Income taxes	68,672	31,611
Recognition of operating lease assets in exchange for lease liabilities	701	12,616
Acquisitions:
Fair value of tangible assets acquired		3,501,273
Other intangible assets acquired		20,791
Liabilities assumed		3,205,694
Net identifiable assets acquired over liabilities assumed		341,440
Common stock issued in acquisition		659,772
Real estate acquired in full or in partial settlement of loans	$ 3,298	$ 1,151