Consolidated Statement of Stockholders' Equity (USD $) In Thousands, except Share data	Total	Equity of the Company Preferred Stock [Member]	Equity of the Company Common Stock [Member]	Equity of the Company Treasury Stock [Member]	Equity of the Company Additional Paid-in Capital [Member]	Equity of the Company Accumulated Other Comprehensive Income (Loss) [Member]	Equity of the Company Retained Earnings [Member]	Noncontrolling Interest [Member]
Beginning balance,value at Dec. 31, 2008	$ 360,894	$ 0	$ 638	$ (228,596)	$ 341,887	$ (33,020)	$ 274,974	$ 5,011
Preferred stock beginning balance, share at Dec. 31, 2008		0
Common stock beginning balance, share at Dec. 31, 2008			63,816,000
Net income	75,566						71,754	3,812
Dividends distributed to noncontrolling interest	(3,690)							(3,690)
Foreign currency translation adjustments	18,231					17,886		345
Derivatives valuation, net of tax	25,647					25,647
Vesting of restricted stock units issued out of treasury, share			307,000
Vesting of restricted stock units issued out of treasury, value	(1,919)		3	3,855	(5,777)
Exercise of stock options, share			621,000
Exercise of stock options, value	6,159		6	7,791	(1,638)
Excess tax benefit from equity-based awards	(1,861)				(1,861)
Equity-based compensation expense	11,640				11,640
Purchases of common stock, share			(2,526,000)
Purchases of common stock, value	(34,766)		(25)	(34,741)
Ending balance,value at Dec. 31, 2009	455,901	0	622	(251,691)	344,251	10,513	346,728	5,478
Preferred stock ending balance, share at Dec. 31, 2009		0
Common stock ending balance, share at Dec. 31, 2009			62,218,000
Net income	53,538						49,874	3,664
Noncontrolling interest (Note 2)	6,000							6,000
Dividends distributed to noncontrolling interest	(4,140)							(4,140)
Foreign currency translation adjustments	8,080					7,990		90
Derivatives valuation, net of tax	2,623					2,623
Vesting of restricted stock units issued out of treasury, share			420,000
Vesting of restricted stock units issued out of treasury, value	(3,072)		5	5,448	(8,525)
Exercise of stock options, share			273,000
Exercise of stock options, value	2,792		3	3,541	(752)
Excess tax benefit from equity-based awards	811				811
Equity-based compensation expense	13,372				13,372
Purchases of common stock, share			(5,036,000)
Purchases of common stock, value	(80,295)		(51)	(80,244)
Other	(792)					(792)
Ending balance,value at Dec. 31, 2010	454,818	0	579	(322,946)	349,157	20,334	396,602	11,092
Preferred stock ending balance, share at Dec. 31, 2010	0	0
Common stock ending balance, share at Dec. 31, 2010	57,875,269		57,875,000
Net income	78,275						74,174	4,101
Dividends distributed to noncontrolling interest	(3,548)							(3,548)
Foreign currency translation adjustments	(12,596)					(12,211)		(385)
Derivatives valuation, net of tax	(12,942)					(12,942)
Vesting of restricted stock units issued out of treasury, share			561,000
Vesting of restricted stock units issued out of treasury, value	(5,393)		5	7,706	(13,104)
Exercise of stock options, share			1,564,000
Exercise of stock options, value	14,762		15	21,633	(6,886)
Excess tax benefit from equity-based awards	5,363				5,363
Equity-based compensation expense	15,856				15,856
Purchases of common stock, share			(3,365,000)
Purchases of common stock, value	(63,693)		(33)	(63,660)
Other	(655)					(655)
Ending balance,value at Dec. 31, 2011	$ 470,247	$ 0	$ 566	$ (357,267)	$ 350,386	$ (5,474)	$ 470,776	$ 11,260
Preferred stock ending balance, share at Dec. 31, 2011	0	0
Common stock ending balance, share at Dec. 31, 2011	56,635,319		56,635,000