CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY (USD $) In Thousands, except Share data, unless otherwise specified	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Loss [Member]	Total
Balance at Dec. 31, 2009	$ 3,140	$ 100,497	$ 22,345	$ (18,109)	$ (4,603)	$ 103,270
Balance (in shares) at Dec. 31, 2009	31,408,778					31,408,778
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			9,647			9,647
Other comprehensive loss					(7,289)	(7,289)
Purchase of treasury stock				(33)		(33)
Deferred compensation		(96)		262		166
Vested restricted stock		(1,004)		1,004		0
Vested restricted stock (in shares)	860
Stock option modification		52				52
Stock option expense		1,020				1,020
Restricted stock expense		645				645
Performance stock expense		157				157
Balance at Dec. 31, 2010	3,140	101,271	31,992	(16,876)	(11,892)	107,635
Balance (in shares) at Dec. 31, 2010	31,409,638					31,409,638
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			10,968			10,968
Other comprehensive loss					(19,695)	(19,695)
Purchase of treasury stock				(329)		(329)
Exercise of stock options	3	142				145
Exercise of stock options (in shares)	31,500
Deferred compensation		(28)		80		52
Vested restricted stock		(911)		911		0
Vested performance stock		(393)		393		0
Stock option expense		1,028				1,028
Restricted stock expense		497				497
Performance stock expense		40				40
Balance at Dec. 31, 2011	3,143	101,646	42,960	(15,821)	(31,587)	100,341
Balance (in shares) at Dec. 31, 2011	31,441,138					31,441,138
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income			62,303			62,303
Other comprehensive loss					(2,504)	(2,504)
Exercise of stock options	26	1,329				1,355
Exercise of stock options (in shares)	263,092
Vested restricted stock		(604)		604		0
Stock option expense		1,303				1,303
Restricted stock expense		446				446
Performance stock expense		53				53
Balance at Dec. 31, 2012	$ 3,169	$ 104,173	$ 105,263	$ (15,217)	$ (34,091)	$ 163,297
Balance (in shares) at Dec. 31, 2012	31,704,230					31,704,230