CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY (USD $) In Thousands, unless otherwise specified	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock, At Cost [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss) [Member]	Comprehensive Income [Member]
Balances at Dec. 31, 2008		$ 389	$ 179,241	$ (31,158)	$ 192,401	$ (6,918)
Balances (in shares) at Dec. 31, 2008		36,224
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Stock-based compensation expense			2,818
Issuance of restricted stock			(754)	1,183
Issuance of restricted stock (in shares)		105
Retired restricted stock			(10)	(15)
Exercise of stock options			(1,537)	2,619
Exercise of stock options (in shares)		221
Repurchase of treasury stock				(1,174)
Repurchase of treasury stock (in shares)		(99)
Income tax benefit on stock-based compensation			750
Change in cumulative translation adjustment						8,276	8,276
Dividends paid					(27,611)
Net income	46,185				46,185		46,185
Total comprehensive income							54,461
Balances at Dec. 31, 2009		389	180,508	(28,545)	210,975	1,358
Balances (in shares) at Dec. 31, 2009		36,451
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Stock-based compensation expense			2,377
Issuance of restricted stock			(420)	1,259
Issuance of restricted stock (in shares)		106
Restricted stock withheld for employee taxes			(367)	(432)
Restricted stock withheld for employee taxes (in shares)		(36)
Exercise of stock options			(1,754)	2,771
Exercise of stock options (in shares)		234
Income tax benefit on stock-based compensation			1,175
Change in cumulative translation adjustment						(2,577)	(2,577)
Net income	42,551				42,551		42,551
Total comprehensive income							39,974
Balances at Dec. 31, 2010	409,268	389	181,519	(24,947)	253,526	(1,219)
Balances (in shares) at Dec. 31, 2010		36,755
Increase (Decrease) in Shareholders' Equity [Roll Forward]
Stock-based compensation expense			1,795
Issuance of restricted stock			(1,371)	1,507
Issuance of restricted stock (in shares)		126
Exercise of stock options			(527)	810
Exercise of stock options (in shares)		68
Return of common stock				(7,890)
Return of common stock (in shares)		(550)
Surrender of fully vested options			(1,115)
Income tax benefit on stock-based compensation			237
Change in cumulative translation adjustment						(2,830)	(2,830)
Net income	54,408				54,408		54,408
Total comprehensive income							51,578
Balances at Dec. 31, 2011	$ 454,292	$ 389	$ 180,538	$ (30,520)	$ 307,934	$ (4,049)
Balances (in shares) at Dec. 31, 2011		36,399