CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018
Cash flows from operating activities:
Net income	$ 77,245	$ 55,305
Adjustments to net income:
Depreciation and amortization expense	4,636	3,717
Provision for credit losses	1,860	4,014
Share-based compensation expense	5,313	3,917
(Gain) loss on sale and disposal of premises and equipment	(170)	52
(Gain) loss on sale of or write down of other real estate owned	(75)	21
Net amortization on securities	2,573	3,622
Net accretion of deferred loan fees/costs and discounts/premiums for loans acquired	12,271	8,444
Gain on sale of investment securities available-for-sale	(639)	(336)
Originations of loans held for sale	(59,801)	(53,064)
Proceeds from the sales of and principal payments from loans held for sale	61,356	72,667
Gain on sale of loans	(2,631)	(6,801)
Deferred income tax expense	1,988	1,699
Change in accrued expenses and other liabilities, net	(11,315)	9,709
Income from bank owned life insurance, net	(1,367)	(961)
Amortization of core deposit intangible	8,717	4,269
Change in accrued interest receivable and other assets, net	(462)	8,299
Net cash provided by operating activities	99,499	114,573
Cash flows from investing activities:
Net decrease in interest-bearing time deposits with financial institutions	3,187	0
Proceeds from sale of other real estate owned	390	108
Loan originations and payments, net	21,562	(115,696)
Proceeds from loans held for sale previously classified as portfolio loans	74,070	21,556
Purchase of loans held for investment	(48,903)	0
Purchase of held-to-maturity securities	0	(14,036)
Principal payments on held-to-maturity securities	2,214	318
Purchase of securities available-for-sale	(400,409)	(181,536)
Principal payments on securities available-for-sale	55,549	47,743
Proceeds from sale or maturity of securities available-for-sale	227,138	20,323
Proceeds from the sale of premises and equipment	11,108	0
Proceeds from bank owned life insurance death benefit	405	0
Purchases of premises and equipment	(5,101)	(4,663)
Change in FHLB, FRB, and other stock, at cost	2,416	(7,883)
Funding of CRA investments	(5,338)	(11,807)
Net cash used in investing activities	(61,712)	(245,573)
Cash flows from financing activities:
Net increase in deposit accounts	203,571	222,464
Net change in short-term borrowings	(86,075)	(146,677)
Repayment of long-term FHLB borrowings	(10,000)	(10,500)
Proceeds from issuance of subordinated debt, net	122,453	0
Cash dividends paid	(27,541)	0
Repurchase and retirement of common stock	(65,969)	0
Proceeds from exercise of stock options	381	1,596
Restricted stock surrendered and canceled	(2,629)	(1,579)
Net cash provided by financing activities	134,191	65,304
Net increase (decrease) in cash and cash equivalents	171,978	(65,696)
Cash and cash equivalents, beginning of period	203,406	197,164
Cash and cash equivalents, end of period	375,384	131,468
Supplemental cash flow disclosures:
Interest paid	39,469	20,053
Income taxes paid	26,634	17,491
Noncash investing activities during the period:
Transfers from portfolio loans to loans held for sale	75,175	24,811
Transfers from loans to other real estate owned	203	0
Recognition of operating lease right-of-use assets	(48,685)	0
Recognition of operating lease liabilities	48,685	0
Receivable on unsettled security sales	$ 0	$ 5,033