Consolidated Statements of Stockholders' Equity (USD $) In Thousands, except Share data	Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Treasury Stock [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Total
Balance at Dec. 31, 2010	$ 20	$ 220,891	$ 133,637	$ (1,291)	$ (524)	$ 352,733
Balance (in Shares) at Dec. 31, 2010	19,568			51
Net income			34,865			34,865
Other comprehensive loss					(281)	(281)
Equity compensation		6,658				6,658
Exercise of stock options		478				478
Exercise of stock options (in Shares)	39
Issuance of shares pursuant to vesting of restricted stock units (in Shares)	176
Net payments for stock issuances and buybacks		77		(975)		(898)
Net payments for stock issuances and buybacks (in Shares)	9			44
Tax impact of stock option exercises and award vesting		(527)				(527)
Balance at Dec. 31, 2011	20	227,577	168,502	(2,266)	(805)	393,028
Balance (in Shares) at Dec. 31, 2011	19,792			95
Net income			38,075			38,075
Other comprehensive loss					(436)	(436)
Equity compensation		8,770				8,770
Exercise of stock options		78				78
Exercise of stock options (in Shares)	11
Issuance of shares pursuant to vesting of restricted stock units (in Shares)	231
Net payments for stock issuances and buybacks		33		(11,602)		(11,569)
Net payments for stock issuances and buybacks (in Shares)	(475)			517
Tax impact of stock option exercises and award vesting		804				804
Balance at Dec. 31, 2012	20	237,262	206,577	(13,868)	(1,241)	428,750
Balance (in Shares) at Dec. 31, 2012	19,559			612
Net income			39,330			39,330
Other comprehensive loss					251	251
Equity compensation		8,786		105		8,891
Exercise of stock options	1	3,102				3,103
Exercise of stock options (in Shares)	159
Issuance of shares pursuant to vesting of restricted stock units (in Shares)	294			(5)
Net payments for stock issuances and buybacks		335		(7,782)		(7,447)
Net payments for stock issuances and buybacks (in Shares)	(247)			246
Tax impact of stock option exercises and award vesting		1,213				1,213
Balance at Dec. 31, 2013	$ 21	$ 250,698	$ 245,907	$ (21,545)	$ (990)	$ 474,091
Balance (in Shares) at Dec. 31, 2013	19,765			853