Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash Flows From Operating Activities:
Net income	$ 40,099	$ 38,989
Adjustments to reconcile net income to net cash provided by (used in) operating activities:
Provision for loan losses	2,076	1,643
Amortization of intangible assets	294	256
Depreciation and amortization of premises and equipment	913	880
Accretion of discount on loans	(297)	(194)
Net amortization (accretion) of premium (discount) on investment securities	513	437
Net amortization (accretion) of premium (discount) on time deposits	(23)	0
Net amortization (accretion) on FHLB advances and other borrowings	0	(526)
Impairment of other real estate owned	492	184
(Gain) loss on available for sale debt securities	240	777
(Gain) loss on sale of loans	(276)	(796)
(Gain) loss on sale of other real estate owned	(105)	(45)
(Gain) loss on sale of premises and equipment	0	(1)
Unrealized (gain) loss on preferred stock and other equity securities	1,644	0
Stock-based compensation	1,871	1,431
Increase in cash surrender value of BOLI	(1,367)	(1,414)
Net change in operating assets and liabilities:
Net change in loans held for sale	(1,816)	(588)
Net change in other assets	4,842	(5,723)
Net change in other liabilities	479	10,630
Net cash provided by operating activities	49,099	44,386
Cash Flows From Investing Activities:
Purchase of equity securities	(14)	(6,005)
Purchase of available for sale debt securities	(247,098)	(167,133)
Sales of available for sale debt securities	35,366	17,728
Paydown and maturities of available for sale debt securities	102,292	67,141
Purchase of FHLB and other bank stock	(22,895)	(32,318)
Sales of FHLB and other bank stock	25,033	28,322
Cash received in acquisition	16,699	0
Net change in loans	(306,721)	(404,462)
Purchase of loans	(1,071)	0
Proceeds from sale of loans	18,128	120,536
Proceeds from sale of other real estate owned	460	1,216
Purchase of premises and equipment	(768)	(519)
Proceeds from the sale of premises and equipment	0	14
Proceeds from life insurance	0	1,763
Net cash used in investing activities	(380,589)	(373,717)
Cash Flows From Financing Activities:
Net change in deposits	430,039	368,700
Net change in FHLB advances	(84,404)	52,450
Net change in repurchase agreements	15,823	(63,508)
Cash paid for withholding taxes on share based payments	(3,666)	0
Exercise of stock options and warrants	7,084	21,665
Other financing costs	(282)	(15)
Net cash provided by financing activities	364,594	379,292
Net Change in Cash and Cash Equivalents	33,104	49,961
Cash and Cash Equivalents at Beginning of Period	115,921	83,876
Cash and Cash Equivalents at End of Period	149,025	133,837
Supplemental Disclosures of Cash Flow Information:
Interest paid	26,030	15,675
Income taxes paid	17	0
Supplemental disclosure of noncash investing and financing activities:
Transfer/adjustments of loans to other real estate owned	(100)
Transfer from loans to other real estate owned		888
Transfers from loans held for sale to portfolio loans	10,683	0
(Purchase) sale of investment securities settled in subsequent period, net	$ (25,023)	$ 6,214