CONDENSED CONSOLIDATED STATEMENTS OF CHANGES IN EQUITY (USD $) In Thousands, except Share data	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Noncontrolling Interest
Beginning Balance at Dec. 31, 2009	$ 857,173	$ 847	$ 47,522	$ 809,618	$ (12,292)	$ 11,478
Beginning Balance (in shares) at Dec. 31, 2009		84,715,000
Net income	210,457			207,879		2,578
Currency translation adjustment	394				(2,544)	2,938
Change in fair value of cash flow hedge, net of tax of $1,353	(2,033)				(2,033)
Comprehensive income	208,818
Issuance of common stock for exercise of options and employee stock purchases (in shares)		1,988,000
Issuance of common stock for exercise of options and employee stock purchases	50,511	20	50,491
Purchase/ cancellation of treasury stock (in Shares)		(1,461,000)
Purchase/ cancellation of treasury stock	(94,335)	(15)	(94,320)
Stock compensation expense	18,565		18,565
Excess tax benefit of stock options exercised	24,687		24,687
Change in noncontrolling interest	14,931					14,931
Ending Balance at Dec. 31, 2010	1,080,350	852	46,945	1,017,497	(16,869)	31,925
Ending Balance (in shares) at Dec. 31, 2010	85,242,387	85,242,000
Net income	172,220			170,463		1,757
Currency translation adjustment	(17,841)				(16,257)	(1,584)
Amounts reclassified into income, net of tax of $162	256				256
Comprehensive income	154,635
Issuance of common stock for exercise of options and employee stock purchases (in shares)		967,000
Issuance of common stock for exercise of options and employee stock purchases	33,821	10	33,811
Purchase/ cancellation of treasury stock (in Shares)	(1,012,856)	(1,013,000)
Purchase/ cancellation of treasury stock	(81,201)	(10)	(81,191)
Stock compensation expense	11,563		11,563
Excess tax benefit of stock options exercised	16,614		16,614
Change in noncontrolling interest	(4,057)		(1,021)			(3,036)
Ending Balance at Sep. 30, 2011	$ 1,211,725	$ 852	$ 26,721	$ 1,187,960	$ (32,870)	$ 29,062
Ending Balance (in shares) at Sep. 30, 2011	85,196,102	85,196,000