CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Cash flows from operating activities:
Net income	$ 210,070	$ 255,058
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization expense	11,164	12,147
Provision for credit losses	1,994	(56,228)
Share-based compensation expense	14,171	9,911
Loss on sales and disposals of premises and equipment	54	179
Net amortization on securities	14,127	17,078
Net (accretion) of discounts/premiums for acquired loans and deferred loan fees/costs	(22,328)	(31,955)
Gain on sales of investment securities available-for-sale	(1,710)	(13,321)
Loss on debt extinguishment	0	180
Gain on sales of loans	(3,087)	(3,094)
Deferred income tax expense	5,561	29,111
Income from bank owned life insurance, net	(7,949)	(6,071)
Amortization of intangible assets	10,543	12,056
Originations of loans held for sale	(57,685)	(34,902)
Proceeds from the sales of and principal payments from loans held for sale	69,478	29,973
Change in accrued expenses and other liabilities, net	6,075	(17,404)
Change in accrued interest receivable and other assets, net	82,719	53,953
Net cash provided by operating activities	333,197	256,671
Cash flows from investing activities:
Net decrease in interest-bearing time deposits with financial institutions	483	137
Loan originations and payments, net	(664,678)	(719,657)
Proceeds from loans held for sale previously classified as portfolio loans	0	1,530
Purchase of loans held for investment	(797)	0
Proceeds from prepayments and maturities of securities held-to-maturity	15,570	7,509
Purchase of securities available-for-sale	(986,997)	(2,079,198)
Proceeds from prepayments and maturities of securities available-for-sale	248,629	429,235
Proceeds from sales of securities available-for-sale	936,413	630,437
Proceeds from the sales of premises and equipment	0	26
Proceeds from surrender of bank owned life insurance	0	1,400
Purchase of bank owned life insurance	0	(150,000)
Purchase of premises and equipment	(4,961)	(6,318)
Change in FHLB, FRB, and other stock, at cost	(2,321)	3
Funding of CRA investments, net	(10,910)	(19,001)
Net cash used in investing activities	(469,569)	(1,903,897)
Cash flows from financing activities:
Net increase in deposit accounts	630,785	1,255,822
Net change in short-term borrowings	(358,000)	140,000
Proceeds from long-term borrowings	400,000	0
Repayments of long-term borrowings	0	(21,503)
Redemption of junior subordinated debt securities	0	(171,153)
Cash dividends paid	(93,806)	(90,747)
Repurchase and retirement of common stock	0	(18,067)
Proceeds from exercise of stock options	759	782
Restricted stock surrendered and canceled	(8,858)	(6,354)
Net cash provided by financing activities	570,880	1,088,780
Net increase (decrease) in cash and cash equivalents	434,508	(558,446)
Cash and cash equivalents, beginning of period	304,703	880,766
Cash and cash equivalents, end of period	739,211	322,320
Supplemental cash flow disclosures:
Interest paid	28,638	29,745
Income taxes paid, net	47,932	56,472
Noncash investing activities during the period:
Transfers from portfolio loans to loans held for sale	0	1,006
Transfers of investment securities from available-for-sale to held-to-maturity	1,019,472	154,456
Recognition of operating lease right-of-use assets	(1,183)	(3,812)
Recognition of operating lease liabilities	$ 1,183	$ 3,812