CONSOLIDATED STATEMENTS OF CASH FLOWS (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 45,169	$ 27,879	$ 76,666	$ 51,147
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization			16,315	14,273
Provision for loan losses	4,918	4,831	6,553	9,094
Net amortization of premium on securities			10,927	12,587
Securities gains, net	(3,580)	259	(5,155)	(1,182)
Unrealized gain on equity securities, net			(370)	(43)
Stock based compensation			3,602	2,770
Loans originated for sale			(165,249)	(317,979)
Proceeds on sales of loans held for sale			161,625	346,083
Net gains on sale of loans held for sale			(7,177)	(8,178)
(Increase) decrease in accrued interest receivable			2,421	(35)
Decrease in prepaid expenses			229	2,263
Increase (decrease) in accrued interest payable			1,021	(25)
Capitalization of servicing rights			(415)	(2,694)
Valuation allowance on servicing rights	364	216	953	218
(Gain)/loss on sales/valuations of assets, net			(10,735)	1,331
Net excess tax benefit from stock based compensation			272	660
Other, net			(29,184)	(16,605)
NET CASH PROVIDED BY OPERATING ACTIVITIES			62,299	93,685
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchase of time deposits in other financial institutions			(248)	(1,000)
Proceeds from the sale of securities available for sale	760,743	243,489	1,194,897	635,735
Proceeds from the redemption of time deposits in other financial institutions			0	8,767
Proceeds from the maturity of and principal paydowns on securities available for sale			178,930	112,166
Proceeds from the maturity of and principal paydowns on securities held to maturity			2,406	8,897
Proceeds from the maturity of and principal paydowns on time deposits in other financial institutions			490	4,862
Proceeds from the sale, maturity of and principal paydowns on other investments			7,992	1,400
Purchase of securities available for sale			(1,148,238)	(733,030)
Purchase of other investments			(4,899)	(1,842)
Net (increase) decrease in loans			77,147	(86,466)
Purchase of bank owned life insurance policies			(16)	0
Proceeds from bank owned life insurance policies			421	0
Proceeds from sale of mortgage servicing rights			33,823	0
Capital expenditures			(3,909)	(9,788)
Net cash and cash equivalents received in acquisitions			38,650	212,197
Proceeds from the sale of equipment			829	622
Net cash expended in divestitures			(49,264)	0
Proceeds on sale of OREO and other repossessed assets			3,825	2,091
NET CASH PROVIDED BY INVESTING ACTIVITIES			332,836	154,611
CASH FLOWS FROM FINANCING ACTIVITIES:
Net increase in demand deposits			4,675	117,456
Net increase in savings deposits			110,498	5,408
Net increase (decrease) in time deposit accounts			29,924	(31,789)
Proceeds on short-term revolving credit line			0	25,000
Net decrease in short-term borrowings			(44,326)	(155,403)
Proceeds from short term FHLB advances			430,888	302,102
Repayments of short term FHLB advances			(531,725)	(266,500)
Proceeds from other borrowings			50	0
Repayments of other borrowings			(15,621)	(44,654)
Purchase of treasury stock			0	(97)
Proceeds from issuance of common stock			408	156
Dividends paid			(11,397)	(7,972)
NET CASH USED BY FINANCING ACTIVITIES			(26,626)	(56,293)
Net increase in cash and cash equivalents			368,509	192,003
Cash and cash equivalents at beginning of year			273,630	196,003	$ 196,003
CASH AND CASH EQUIVALENTS AT END OF PERIOD	$ 642,139	$ 388,006	642,139	388,006	$ 273,630
Supplemental disclosures:
Cash paid for income/franchise taxes			19,495	8,254
Cash paid for interest			37,099	21,655
Loans transferred to OREO			4,655	2,264
Transfer of premises from premises, furniture and equipment, net, to premises, furniture and equipment held for sale			2,568	2,501
Transfer of premises from premises, furniture and equipment held for sale to premises, furniture and equipment, net,			1,564	0
Deposits transferred to held for sale			76,968	0
Loans transferred to held for sale			32,111	0
Securities transferred from held to maturity to available for sale			148,030	0
Purchases of securities available for sale, accrued, not settled			37,373	0
Stock consideration granted for acquisitions			$ 92,258	$ 238,075