Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Operating activities:
Net income	$ 68,320	$ 40,554	$ 44,811
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation of premises and equipment, and amortization	7,014	6,787	6,474
Amortization of intangible assets	3,499	1,389	1,377
Provision for (benefit from) loan losses	2,583	89	(5,970)
Amortization of investment securities premium, net	2,512	3,200	4,926
Gain on sale of investment securities	(207)	(961)
Originations of loans for resale	(84,245)	(114,107)	(142,619)
Proceeds from sale of loans originated for resale	86,988	114,788	144,062
Gain on sale of loans	(2,371)	(3,109)	(4,037)
Change in market value of mortgage servicing rights	146	718	2,184
Provision for losses on foreclosed assets	89	162	140
Gain on sale of foreclosed assets	(408)	(711)	(262)
Loss on disposal of fixed assets	185	142	929
Gain on sale of premises held for sale		(3)
Increase in cash value of life insurance	(2,718)	(2,685)	(2,717)
Life insurance proceeds in excess of cash value		(108)	(238)
Loss on marketable equity securities	64
Equity compensation vesting expense	1,462	1,586	1,467
Equity compensation tax effect			(155)
Deferred income tax expense	2,600	12,473	3,190
Change in:
Interest receivable	(5,640)	(1,745)	(1,241)
Interest payable	1,067	112	44
Other assets and liabilities, net	10,129	(3,190)	(4,139)
Net cash from operating activities	91,069	55,381	48,226
Investing activities:
Cash acquired in acquisition, net of consideration paid	30,613		156,316
Proceeds from maturities of securities available for sale	73,014	63,942	71,684
Proceeds from maturities of securities held to maturity	68,937	86,371	121,666
Proceeds from sale of available for sale securities	293,279	25,757
Purchases of securities available for sale	(436,678)	(265,806)	(247,717)
Net redemption of restricted equity securities	7,429
Loan origination and principal collections, net	(173,752)	(247,837)	(251,479)
Loans purchased		(11,567)	(22,503)
Proceeds from sale of loans other than loans originated for resale			37,880
Proceeds from sale of foreclosed assets	2,527	2,872	4,010
Proceeds from sale of premises held for sale		3,338
Proceeds from sale of premises and equipment	63		1,682
Purchases of premises and equipment	(7,435)	(15,164)	(10,930)
Life insurance proceeds		649
Net cash from investing activities	(142,003)	(357,445)	(139,391)
Financing activities:
Net change in deposits	365,400	113,571	103,063
Net change in other borrowings	(271,327)	104,673	5,165
Equity compensation tax effect			155
Repurchase of common stock	(2,483)	(1,629)	(1,890)
Dividends paid	(18,769)	(15,131)	(13,695)
Exercise of stock options	218	396	518
Net cash from financing activities	73,039	201,880	93,316
Net change in cash and cash equivalents	22,105	(100,184)	2,151
Cash and cash equivalents at beginning of year	205,428	305,612	303,461
Cash and cash equivalents at end of year	227,533	205,428	305,612
Supplemental disclosure of noncash activities:
Unrealized (loss) gain on securities available for sale	(17,627)	5,461	(11,015)
Loans transferred to foreclosed assets	1,262	1,563	2,505
Market value of shares tendered in-lieu of cash to pay for exercise of options and/or related taxes	1,486	2,225	5,988
Supplemental disclosure of cash flow activity:
Cash paid for interest expense	11,805	5,609	5,677
Cash paid for income taxes	14,525	$ 21,170	27,575
Assets acquired in acquisition and goodwill, net	1,463,200		161,231
Liabilities assumed in acquisition	$ 1,172,068		$ 161,231