Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($)	6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015
Cash flows from operating activities
Net income	$ 15,983,000	$ 13,204,000
Adjustments to reconcile net income to net cash from operating activities
Depreciation and amortization	4,275,000	5,588,000
Accretion of acquired loans	(2,251,000)	(2,910,000)
Provision for loan losses	1,700,000	(1,000,000)
Stock-based compensation expense	616,000	359,000
Stock grants to directors for retainer fee	327,000	402,000
Proceeds from sales of mortgage loans held for sale	46,441,000	57,735,000
Origination of mortgage loans held for sale	(46,715,000)	(56,853,000)
Net gain from sales of mortgage loans held for sale	(1,290,000)	(1,706,000)
Gain on trust preferred securities repurchase	(2,970,000)	0
Net gain from sales and valuation write-down of foreclosed assets	(322,000)	(71,000)
Net gain from sales and valuation write-down of former bank premises	(10,000)	0
Net (gain) loss from sales of fixed assets	171,000	(10,000)
Net (gain) loss from sales of available for sale securities	1,000	(5,000)
Earnings on bank owned life insurance	(584,000)	(548,000)
Net change in:
Accrued interest receivable	568,000	212,000
Other assets	(120,000)	(188,000)
Accrued interest and other liabilities	(13,000)	896,000
Net cash from operating activities	15,807,000	15,105,000
Cash flows from investing activities
Loan originations and payments, net	(99,276,000)	(82,399,000)
Purchases of securities available for sale	(60,873,000)	(4,868,000)
Proceeds from maturities, calls and repayments of securities available for sale	86,872,000	62,135,000
Proceeds from sales of securities available for sale	264,000	665,000
Proceeds from sales of foreclosed assets	1,371,000	1,131,000
Proceeds from sales of former bank premises	46,000	0
Proceeds from FHLB stock redemption	0	6,132,000
Purchases of FHLB stock	(459,000)	0
Purchases of bank owned life insurance	(7,000,000)	0
Net purchases of premises and equipment	(307,000)	(589,000)
Net cash for investing activities	(79,362,000)	(17,793,000)
Cash flows from financing activities
Net decrease in time deposits	(17,540,000)	(84,451,000)
Net increase in all other deposits	21,876,000	87,505,000
Net decrease in securities sold under agreements to repurchase	(18,081,000)	(15,488,000)
Maturities of Federal Home Loan Bank advances	0	(6,000,000)
Proceeds from Federal Home Loan Bank advances	110,000,000	0
Proceeds from stock option exercises	379,000	275,000
Employee stock purchase plan	18,000	23,000
Dividend reinvestment plan	909,000	283,000
Repurchase of common stock shares	(3,732,000)	(9,110,000)
Repurchase of trust preferred securities	(8,030,000)	0
Payment of cash dividends to common shareholders	(5,152,000)	(4,656,000)
Net cash from (for) financing activities	80,647,000	(31,619,000)
Net change in cash and cash equivalents	17,092,000	(34,307,000)
Cash and cash equivalents at beginning of period	89,891,000	172,738,000
Cash and cash equivalents at end of period	106,983,000	138,431,000
Supplemental disclosures of cash flows information
Interest	6,016,000	5,564,000
Federal income tax	6,700,000	5,700,000
Noncash financing and investing activities:
Transfers from loans to foreclosed assets	236,000	1,098,000
Transfers from bank premises to other real estate owned	$ 371,000	$ 0