CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (USD $) In Thousands, except Share data, unless otherwise specified	Common Stock [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total
Balance at Dec. 31, 2009	$ 17,890	$ 160,230	$ (2,448)	$ 175,672
Balance (in shares) at Dec. 31, 2009	23,681,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	18,075	0	18,075
Other comprehensive income	0	0	2,448	2,448
Dividends declared	0	(7,833)	0	(7,833)
Dividends reinvested in common stock	520	0	0	520
Dividends reinvested in common stock (in shares)	29,000
Stock based compensation	792	0	0	792
Common stock issued through exercise of incentive stock options	561	0	0	561
Common stock issued through exercise of incentive stock options (in shares)	57,000
Net excess tax benefit from stock options exercised	70	0	0	70
Balance at Dec. 31, 2010	19,833	170,472	0	190,305
Balance (in shares) at Dec. 31, 2010	23,767,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	12,993	0	12,993
Dividends declared	0	(7,849)	0	(7,849)
Dividends reinvested in common stock	529	0	0	529
Dividends reinvested in common stock (in shares)	51,000
Stock based compensation	1,718	0	0	1,718
Common stock issued through exercise of incentive stock options	37	0	0	37
Common stock issued through exercise of incentive stock options (in shares)	5,000
Net excess tax benefit from stock options exercised	5	0	0	5
Common stock issued for share awards	0	0	0	0
Common stock issued for share awards (in shares)	19,000
Common stock issued	13	0	0	13
Common stock issued (in shares)	1,000
Common stock repurchased	(92)	0	0	(92)
Common stock repurchased (in shares)	(5,000)
Balance at Dec. 31, 2011	22,043	175,616	0	197,659
Balance (in shares) at Dec. 31, 2011	23,838,000			23,838,000
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	0	16,303	0	16,303
Other comprehensive income	0	0	(863)	(863)
Dividends declared	0	(7,896)	0	(7,896)
Dividends reinvested in common stock	493	0	0	493
Dividends reinvested in common stock (in shares)	37,000
Stock based compensation	1,842	0	0	1,842
Common stock issued through exercise of incentive stock options	404	0	0	404
Common stock issued through exercise of incentive stock options (in shares)	55,000
Net excess tax benefit from stock options exercised	39	0	0	39
Common stock issued for share awards	0	0	0	0
Common stock issued for share awards (in shares)	45,000
Common stock issued	10	0	0	10
Common stock issued (in shares)	1,000
Common stock repurchased	(143)	0	0	(143)
Common stock repurchased (in shares)	(13,000)
Balance at Dec. 31, 2012	$ 24,688	$ 184,023	$ (863)	$ 207,848
Balance (in shares) at Dec. 31, 2012	23,962,000			23,962,000