Consolidated Statements of Cash Flows (unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021
Cash Flows From Operating Activities
Net income	$ 87,399	$ 149,604
Adjustments to reconcile net income to cash provided by operating activities:
Depreciation	17,742	14,068
Amortization of other intangible assets	11,981	5,984
Amortization of tax credit investments	3,041	3,015
Net premium amortization on investment securities	9,413	7,526
Accretion income related to acquired loans	(44,083)	(9,781)
Share-based compensation expense	14,097	3,563
Provision for credit losses	106,814	(22,285)
Debt securities (gains) losses, net	(257)	(2,685)
Net (gains) losses on sales of loans and other assets	(4,010)	(18,202)
Increase in cash surrender value of company-owned life insurance	(8,095)	(5,497)
Residential real estate loans originated for sale	(364,018)	(645,624)
Proceeds from sales of residential real estate loans	395,829	677,888
(Increase) decrease in interest receivable	(19,468)	(288)
(Increase) decrease in other assets	127,991	40,951
Increase (decrease) in accrued expenses and other liabilities	104,456	(33,062)
Net cash flows provided by (used in) operating activities	438,832	165,175
Cash Flows From Investing Activities
Cash received (paid) from merger, net	1,912,629	0
Purchases of investment securities available-for-sale	(1,276,205)	(1,801,957)
Purchases of investment securities held-to-maturity	(117,141)	0
Purchases of Federal Home Loan Bank/Federal Reserve Bank stock	(97,359)	0
Purchases of equity securities	(1,417)	0
Proceeds from maturities, prepayments, and calls of investment securities available-for-sale	659,922	820,305
Proceeds from sales of investment securities available-for-sale	12,742	67,715
Proceeds from maturities, prepayments, and calls of investment securities held-to-maturity	30,744	0
Proceeds from sales of Federal Home Loan Bank/Federal Reserve Bank stock	83,947	44
Proceeds from sales of equity securities	49,709	325
Loan originations and payments, net	(1,524,289)	11,924
Proceeds from company-owned life insurance death benefits	2,849	2,042
Proceeds from sales of premises and equipment and other assets	2,751	7,632
Purchases of premises and equipment and other assets	(17,459)	(34,411)
Net cash flows provided by (used in) investing activities	(278,577)	(926,381)
Net increase (decrease) in:
Deposits	(279,624)	831,458
Federal funds purchased and interbank borrowings	1,285	357
Securities sold under agreements to repurchase	(51,296)	(35,037)
Other borrowings	53,136	12,428
Payments for maturities of Federal Home Loan Bank advances	(1,100,005)	(145,005)
Payments for modification of Federal Home Loan Bank advances	0	(2,156)
Proceeds from Federal Home Loan Bank advances	1,350,000	50,000
Cash dividends paid	(87,733)	(46,397)
Common stock repurchased	(70,400)	(3,305)
Common stock issued	327	282
Net cash flows provided by (used in) financing activities	(184,310)	662,625
Net increase (decrease) in cash and cash equivalents	(24,055)	(98,581)
Cash and cash equivalents at beginning of period	822,019	589,712
Cash and cash equivalents at end of period	797,964	491,131
Supplemental cash flow information:
Total interest paid	30,904	22,368
Total income taxes paid (net of refunds)	(183)	3,526
Investment securities purchased but not settled	0	8,046
Securities transferred from available-for-sale to held-to-maturity	2,986,736	0
Operating lease right-of-use assets obtained in exchange for lease obligations	3,141	499
Finance lease right-of-use assets obtained in exchange for lease obligations	209	4,994
Common Stock
Supplemental cash flow information:
Issuance of common stock	2,446,312	0
Preferred Stock
Supplemental cash flow information:
Issuance of common stock	$ 243,870	$ 0