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, 2012	$ 284,277	$ 91,332	$ 62,101	$ 164,823	$ (6,920)	$ (27,059)
Beginning balance, shares at Dec. 31, 2012		16,770,232
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	21,189	$ 0	0	21,189	0	0
Other comprehensive loss, net of income tax benefit	(3,035)	0	0	0	(3,035)	0
Cash dividends declared ($0.80 per share)	(13,286)	0	0	(13,286)	0	0
Stock issued under dividend reinvestment and employee stock purchase plans and other employee benefit programs	2,422	$ 0	20	(32)	0	2,434
Stock issued under dividend reinvestment and employee stock purchase plans and other employee benefit programs, shares		132,681
Repurchase of cancelled restricted stock awards	0	$ 0	519	0	0	(519)
Repurchase of cancelled restricted stock awards, shares		(29,533)
Stock-based compensation	978	$ 0	978	0	0	0
Net tax deficiency on stock-based compensation	(27)	0	(27)	0	0	0
Purchases of treasury stock	(12,012)	$ 0	0	0	0	(12,012)
Purchases of treasury stock, shares		(655,609)
Restricted stock awards granted	0	$ 0	(1,174)	(92)	0	1,266
Restricted stock awards granted, shares		70,041
Ending balance at Dec. 31, 2013	280,506	$ 91,332	62,417	172,602	(9,955)	(35,890)
Ending balance, shares at Dec. 31, 2013		16,287,812
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	22,231	$ 0	0	22,231	0	0
Other comprehensive loss, net of income tax benefit	(4,507)	0	0	0	(4,507)	0
Cash dividends declared ($0.80 per share)	(12,982)	0	0	(12,982)	0	0
Stock issued under dividend reinvestment and employee stock purchase plans and other employee benefit programs	2,462	$ 0	43	0	0	2,419
Stock issued under dividend reinvestment and employee stock purchase plans and other employee benefit programs, shares		124,151
Exercise of stock options	310	$ 0	(5)	0	0	315
Exercise of stock options, shares		17,334
Repurchase of cancelled restricted stock awards	0	$ 0	735	0	0	(735)
Repurchase of cancelled restricted stock awards, shares		(43,452)
Stock-based compensation	1,141	$ 0	1,141	0	0	0
Net tax deficiency on stock-based compensation	(2)	0	(2)	0	0	0
Purchases of treasury stock	(4,605)	$ 0	0	0	0	(4,605)
Purchases of treasury stock, shares		(238,542)
Restricted stock awards granted	0	$ 0	(1,349)	0	0	1,349
Restricted stock awards granted, shares		74,304
Ending balance at Dec. 31, 2014	284,554	$ 91,332	62,980	181,851	(14,462)	(37,147)
Ending balance, shares at Dec. 31, 2014		16,221,607
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	27,268	$ 0	0	27,268	0	0
Other comprehensive loss, net of income tax benefit	(2,246)	0	0	0	(2,246)	0
Cash dividends declared ($0.80 per share)	(15,673)	0	0	(15,673)	0	0
Stock issued under dividend reinvestment and employee stock purchase plans and other employee benefit programs	2,434	$ 0	52	0	0	2,382
Stock issued under dividend reinvestment and employee stock purchase plans and other employee benefit programs, shares		123,391
Stock Issued During Period, Value, Acquisitions	76,666	$ 18,939	57,727	0	0	0
Stock Issued During Period, Shares, Acquisitions		3,787,866
Exercise of stock options	$ 461	$ 0	(54)	0	0	515
Exercise of stock options, shares	27,999	27,999
Repurchase of cancelled restricted stock awards	$ 0	$ 0	318	0	0	(318)
Repurchase of cancelled restricted stock awards, shares		(19,934)
Stock-based compensation	1,421	$ 0	1,421	0	0	0
Net tax deficiency on stock-based compensation	31	0	31	0	0	0
Purchases of treasury stock	(13,342)	$ 0	0	0	0	(13,342)
Purchases of treasury stock, shares		(675,754)
Restricted stock awards granted	0	$ 0	(1,195)	0	0	1,195
Restricted stock awards granted, shares		65,755
Ending balance at Dec. 31, 2015	$ 361,574	$ 110,271	$ 121,280	$ 193,446	$ (16,708)	$ (46,715)
Ending balance, shares at Dec. 31, 2015	19,530,930	19,530,930