CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 47,958	$ 34,612	$ 98,129	$ 111,278
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization			20,726	23,561
Provision for Loan and Lease Losses			49,994	11,754
Net amortization of premium on securities			9,925	15,959
Securities gains, net	(1,300)	(2,013)	(4,964)	(7,168)
Unrealized gain on equity securities, net			(604)	(514)
Stock based compensation			5,551	4,833
Loans originated for sale			(461,723)	(289,877)
Proceeds on sales of loans held for sale			443,913	289,769
Net gains on sale of loans held for sale			(21,411)	(11,545)
(Increase) decrease in accrued interest receivable			(7,955)	932
(Increase) decrease in prepaid expenses			408	(3,611)
Increase (decrease) in accrued interest payable			(1,461)	1,905
Gain on extinguishment of debt			0	(375)
Capitalization of servicing rights			(2,633)	(756)
Valuation allowance on servicing rights	120	626	1,676	1,579
(Gain) loss on sales/valuations of assets, net			2,480	(10,378)
Net excess tax (expense) benefit from stock based compensation			(93)	270
Other, net			(48,914)	(40,706)
NET CASH PROVIDED BY OPERATING ACTIVITIES			83,044	96,910
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of time deposits in other financial institutions			(8)	(254)
Proceeds from the sale of securities available for sale	306,383	290,877	818,022	1,485,773
Proceeds from the sale of securities held to maturity			1,056	0
Proceeds from the maturity of and principal paydowns on securities available for sale			400,565	265,500
Proceeds from the maturity of and principal paydowns on securities held to maturity			3,235	2,938
Proceeds from the maturity of time deposits in other financial institutions			593	1,215
Proceeds from the sale, maturity of and principal paydowns on other investments			6,297	10,297
Purchase of securities available for sale			(2,777,981)	(1,984,228)
Purchase of other investments			(10,916)	(4,957)
Net increase in loans			(746,723)	(47,023)
Purchase of bank owned life insurance policies			(208)	(16)
Proceeds from bank owned life insurance policies			606	421
Proceeds from sale of mortgage servicing rights			0	33,823
Capital expenditures			(13,178)	(8,389)
Net cash and cash equivalents received in acquisitions			0	38,650
Proceeds from the sale of equipment			3,339	1,277
Net cash expended in divestitures			0	(49,264)
Proceeds on sale of OREO and other repossessed assets			2,559	6,907
NET CASH USED BY INVESTING ACTIVITIES			(2,312,742)	(247,330)
CASH FLOWS FROM FINANCING ACTIVITIES:
Net increase in demand deposits			1,478,704	159,044
Net increase in savings deposits			434,726	347,749
Net decrease in time deposit accounts			(190,651)	(397)
Net increase (decrease) in short-term borrowings			205,277	(43,733)
Proceeds from short term advances			541,545	430,888
Repayments of short term advances			(622,742)	(531,725)
Proceeds from other borrowings			254,833	50
Repayments of other borrowings			(7,399)	(17,769)
Payments for Repurchase of Warrants			0	(2,125)
Net proceeds from the issuance of preferred stock			110,705	0
Proceeds from issuance of common stock			2,150	576
Dividends paid			(24,529)	(18,001)
NET CASH PROVIDED BY FINANCING ACTIVITIES			2,182,619	324,557
Net increase (decrease) in cash and cash equivalents			(47,079)	174,137
Cash and cash equivalents at beginning of year			378,734	273,630	$ 273,630
CASH AND CASH EQUIVALENTS AT END OF PERIOD	$ 331,655	$ 447,767	331,655	447,767	$ 378,734
Supplemental disclosures:
Cash paid for income/franchise taxes			26,701	30,523
Cash paid for interest			38,088	58,297
Loans transferred to OREO			1,706	7,421
Transfer of premises from premises, furniture and equipment, net, to premises, furniture and equipment held for sale			0	2,568
Transfer of premises from premises, furniture and equipment held for sale to premises, furniture and equipment, net			450	1,564
Deposits transferred to held for sale			0	76,968
Loans transferred to held for sale			0	32,111
Securities transferred from held to maturity to available for sale			0	148,030
Purchases of securities available for sale, accrued, not settled			4,792	22,879
Transfer of available for sale securities to held to maturity securities			462	0
Purchases of loans held to maturity accrued, not settled			9,600	0
Stock consideration granted for acquisitions			$ 0	$ 92,258