Consolidated Statements of Stockholders' Equity (unaudited) - USD ($) $ in Thousands	Common Stock	Surplus	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Loss	Total
Balance at Dec. 31, 2016	$ 191	$ 329,427	$ 91,594	$ (161)	$ (13,064)	$ 407,987
Increase (Decrease) in Stockholders' Equity
Net income			18,012			18,012
Shares issued under the dividend reinvestment plan		469				469
Shares issued for trust preferred securities conversions (529,292 shares)	5	14,944				14,949
Stock awards granted and distributed	1	(416)		415
Stock awards forfeited		20		(20)
Repurchase of surrendered stock from vesting of restricted stock awards				(264)		(264)
Share based compensation expense		1,324				1,324
Cash dividend declared, $0.46 per share			(9,103)			(9,103)
Other comprehensive income (loss), net of deferred income taxes					2,333	2,333
Balance at Jun. 30, 2017	197	345,768	100,503	(30)	(10,731)	435,707
Balance at Dec. 31, 2017	197	347,691	96,547	(296)	(14,939)	429,200
Increase (Decrease) in Stockholders' Equity
Net income			18,816			18,816
Shares issued under the dividend reinvestment plan		468				468
Stock awards granted and distributed	1	(523)		522
Stock awards forfeited		115		(115)
Repurchase of surrendered stock from vesting of restricted stock awards				(552)		(552)
Share based compensation expense		1,787				1,787
Cash dividend declared, $0.46 per share			(9,157)			(9,157)
Other comprehensive income (loss), net of deferred income taxes					(807)	(807)
Balance at Jun. 30, 2018	$ 198	$ 349,538	$ 106,206	$ (441)	$ (15,746)	$ 439,755