Condensed Consolidated Statement of Stockholders' Equity (Unaudited) (USD $) In Thousands, except Share data, unless otherwise specified	Total	Common Stock	Treasury Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Loss
Beginning Balance, Value at Dec. 31, 2012	$ 362,155	$ 3,709	$ (76)	$ 164,346	$ 201,094	$ (6,918)
Beginning Balance, Issued Shares at Dec. 31, 2012	37,131,777	37,131,777
Beginning Balance, Treasury Shares at Dec. 31, 2012			(40,509)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	17,344				17,344
Cumulative translation adjustment	(518)					(518)
Vesting of restricted stock, Shares		31,449
Vesting of restricted stock, Value	0	3		(3)
Exercise of stock options, Shares		79,044
Exercise of stock options, Value	553	8		545
Share based compensation	511			511
Tax benefit related to share-based compensation	0			0
Forfeiture of certain shares to satisfy exercise costs and the recipients income tax obligations related to stock options exercised and restricted stock vested, Shares		(33,631)
Forfeiture of certain shares to satisfy exercise costs and the recipients income tax obligations related to stock options exercised and restricted stock vested, Value	(564)	(3)		(561)
Dividends paid	(2,794)				(2,794)
Ending Balance, Value at Mar. 31, 2013	$ 376,687	$ 3,717	$ (76)	$ 164,838	$ 215,644	$ (7,436)
Ending Balance, Issued Shares at Mar. 31, 2013	37,208,639	37,208,639
Ending Balance, Treasury Shares at Mar. 31, 2013			(40,509)