CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020
Cash flows from operating activities:
Net income	$ 236,222	$ 182,869
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Depreciation and amortization	27,681	29,608
Stock-based compensation	10,690	8,199
Provision for credit losses	17,403	75,839
Net amortization of premiums and accretion of discounts on securities and borrowings	14,112	15,305
Amortization of other intangible assets	11,455	12,151
(Gains) losses on securities transactions, net	(476)	81
Proceeds from sales of loans held for sale	690,844	408,785
Gains on sales of loans, net	(13,574)	(12,887)
Originations of loans held for sale	(541,627)	(443,684)
(Gains) losses on sales of assets, net	(36)	178
Loss on extinguishment of debt	8,406	0
Net change in:
Trading debt securities	(21,216)	0
Cash surrender value of bank owned life insurance	(4,806)	(8,965)
Accrued interest receivable	7,162	(17,170)
Other assets	131,345	(426,776)
Accrued expenses and other liabilities	(119,331)	166,490
Net cash provided by (used in) operating activities	454,254	(9,977)
Cash flows from investing activities:
Net loan originations and purchases	(264,512)	(2,568,893)
Equity securities:
Purchases	(2,482)	(5,365)
Sales	649	0
Held to maturity debt securities:
Purchases	(744,868)	(107,136)
Maturities, calls and principal repayments	372,397	301,004
Available for sale debt securities:
Purchases	(87,366)	(302,071)
Sales	41,134	0
Maturities, calls and principal repayments	287,901	213,348
Death benefit proceeds from bank owned life insurance	3,850	13,751
Proceeds from sales of real estate property and equipment	2,747	8,202
Proceeds from sales of loans held for investment	4,498	30,020
Purchases of real estate property and equipment	(12,207)	(14,469)
Net cash used in investing activities	(398,259)	(2,431,609)
Cash flows from financing activities:
Net change in deposits	1,259,172	2,151,400
Net change in short-term borrowings	(293,580)	989,600
Proceeds from issuance of long-term borrowings, net	295,934	838,388
Repayments of long-term borrowings	(710,595)	(53,418)
Cash dividends paid to preferred shareholders	(6,344)	(6,344)
Cash dividends paid to common shareholders	(90,201)	(89,122)
Purchase of common shares to treasury	(684)	(4,924)
Common stock issued, net	6,194	1,140
Other, net	(333)	(264)
Net cash provided by financing activities	459,563	3,826,456
Net change in cash and cash equivalents	515,558	1,384,870
Cash and cash equivalents at beginning of year	1,329,205	434,687
Cash and cash equivalents at end of period	1,844,763	1,819,557
Supplemental disclosures of cash flow information:
Interest on deposits and borrowings	82,596	178,337
Federal and state income taxes	117,562	14,731
Supplemental schedule of non-cash investing activities:
Transfer of loans to other real estate owned	141	2,750
Transfer of loans to loans held for sale	0	30,020
Lease right of use assets obtained in exchange for operating lease liabilities	$ 1,993	$ 6,407