Consolidated Statements of Changes in Shareholders' Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive (Loss) Income [Member]	Treasury Stock [Member]
Beginning balance at Dec. 31, 2014	$ 284,554	$ 91,332	$ 62,980	$ 181,851	$ (14,462)	$ (37,147)
Beginning balance, shares at Dec. 31, 2014		16,221,607
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	12,582	$ 0	0	12,582	0	0
Other comprehensive income, net of income tax	(708)	0	0	0	(708)	0
Cash dividends declared ($0.40 per share)	(7,902)	0	0	(7,902)	0	0
Stock issued under dividend reinvestment and employee stock purchase plans	1,250	$ 0	30	(1)	0	1,221
Stock issued under dividend reinvestment and employee stock purchase plans, shares		63,502
Issuance of common stock, acquisition	76,666	$ 18,939	57,727	0	0	0
Issuance of common stock, acquisition (shares)		3,787,866
Exercise of stock options	241	$ 0	(27)	0	0	268
Exercise of stock options, shares		14,666
Repurchase of cancelled restricted stock awards	0	$ 0	277	0	0	(277)
Repurchase of cancelled restricted stock awards, shares		(17,684)
Stock-based compensation	813	$ 0	813	0	0	0
Purchases of treasury stock	(11,310)	$ 0	0	0	0	(11,310)
Purchases of treasury stock, shares		(575,771)
Restricted stock awards granted	0	$ 0	(1,195)	0	0	1,195
Restricted stock awards granted, shares		65,755
Ending balance at Jun. 30, 2015	356,186	$ 110,271	120,605	186,530	(15,170)	(46,050)
Ending balance, shares at Jun. 30, 2015		19,559,941
Beginning balance at Dec. 31, 2015	361,574	$ 110,271	121,280	193,446	(16,708)	(46,715)
Beginning balance, shares at Dec. 31, 2015		19,530,930
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	12,529	$ 0	0	12,529	0	0
Other comprehensive income, net of income tax	2,338	0	0	0	2,338	0
Cash dividends declared ($0.40 per share)	(7,819)	0	0	(7,819)	0	0
Stock issued under dividend reinvestment and employee stock purchase plans	1,231	$ 0	25	0	0	1,206
Stock issued under dividend reinvestment and employee stock purchase plans, shares		61,281
Exercise of stock options	377	$ 0	(45)	0	0	422
Exercise of stock options, shares		22,667
Repurchase of cancelled restricted stock awards	0	$ 0	241	0	0	(241)
Repurchase of cancelled restricted stock awards, shares		(14,250)
Stock-based compensation	944	$ 0	944	0	0	0
Net tax benefit/deficiency on stock-based compensation	37	0	37	0	0	0
Purchases of treasury stock	(2,051)	$ 0	0	0	0	(2,051)
Purchases of treasury stock, shares		(101,250)
Restricted stock awards granted	0	$ 0	(1,083)	0	0	1,083
Restricted stock awards granted, shares		58,580
Ending balance at Jun. 30, 2016	$ 369,160	$ 110,271	$ 121,399	$ 198,156	$ (14,370)	$ (46,296)
Ending balance, shares at Jun. 30, 2016		19,557,958