CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2018	Dec. 31, 2017		Dec. 31, 2016
Cash flows from operating activities:
Net income		$ 80,411	$ 57,330		$ 52,084
Adjustments to reconcile net income to net cash from operating activities:
Depreciation		5,654	5,119		4,229
Provision for loan losses		6,400	3,000		1,150
Net loss on sale and write down of other real estate owned		16	12		17
Amortization of loan servicing rights		503	599		598
Loans originated for sale		(49,816)	(54,188)		(69,998)
Net gain on sales of loans		(1,713)	(1,749)		(2,047)
Proceeds from sale of loans		51,715	57,621		68,692
Net loss on sale of premises and equipment		1	79		160
Net (gain) loss on sales and calls of securities available for sale	[1]	50	(32)	[2]	(66)	[2]
Net securities amortization		3,177	3,114		2,860
Stock based compensation expense		5,608	5,698		4,210
Earnings on life insurance		(1,244)	(1,768)		(1,392)
Gain on life insurance		(206)	0		0
Tax benefit of stock award issuances		(761)	(964)		(669)
Net change:
Interest receivable and other assets		(3,301)	787		(1,386)
Interest payable and other liabilities		8,481	2,584		3,757
Total adjustments		24,564	19,912		10,115
Net cash from operating activities		104,975	77,242		62,199
Cash flows from investing activities:
Proceeds from sale of securities available for sale		15,302	40,877		12,095
Proceeds from maturities, calls and principal paydowns of securities available for sale		53,817	61,745		69,343
Purchases of securities available for sale		(126,551)	(139,252)		(116,196)
Purchase of life insurance		(423)	(580)		(3,390)
Net increase in total loans		(101,670)	(347,217)		(391,145)
Proceeds from sales of land, premises and equipment		461	10		28
Purchases of land, premises and equipment		(7,968)	(9,582)		(9,825)
Purchase of Federal Home Loan Bank Stock		0	(2,250)		(3,854)
Proceeds from sales of other real estate owned		21	199		136
Proceeds from life insurance		569	0		360
Net cash from investing activities		(166,442)	(396,050)		(442,448)
Cash flows from financing activities:
Net increase in total deposits		35,410	430,743		394,491
Net increase/(decrease) in short-term borrowings		174,903	100,607		(19,577)
Proceeds on long-term borrowings		0	95,000		180,000
Payments on long-term borrowings		(80,030)	(275,002)		(70,002)
Common dividends paid		(25,278)	(21,396)		(18,200)
Preferred dividends paid		(13)	(13)		(13)
Proceeds (Payments) related to equity incentive plans		(2,435)	(1,736)		614
Purchase of treasury stock		(463)	(495)		(458)
Sales of treasury stock		115	0		0
Net cash from financing activities		102,209	327,708		466,855
Net change in cash and cash equivalents		40,742	8,900		86,606
Cash and cash equivalents at beginning of the year		176,180	167,280		80,674
Cash and cash equivalents at end of the year		216,922	176,180		167,280
Cash paid during the year for:
Interest		43,606	29,171		18,567
Income taxes		19,033	29,120		21,613
Supplemental non-cash disclosures:
Loans transferred to other real estate owned		316	88		105
Security purchased not settled		0	0		1,459
Property transferred to held for sale		$ 221	$ 0		$ 0

[1] Not within scope of ASC 606

[2] The Company elected the modified retrospective approach of adoption; therefore, prior period balances are presented under legacy GAAP and may not be comparable to current year presentation. As a result of this new standard, the only revenue streams with changes in reporting in the current periods compared to the prior year comparable periods are loan and service fees and other income.