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	(94,335)	(15)	(94,320)
Purchase/ cancellation of treasury stock (in Shares)		(1,461,000)
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	112,476			111,216		1,260
Currency translation adjustment	17,793				16,411	1,382
Amounts reclassified into income, net of tax of $108	171				171
Comprehensive income	130,440
Issuance of common stock for exercise of options and employee stock purchases (in shares)		856,000
Issuance of common stock for exercise of options and employee stock purchases	30,485	9	30,476
Purchase/ cancellation of treasury stock	(4,303)	(1)	(4,302)
Purchase/ cancellation of treasury stock (in Shares)		(50,000)
Stock compensation expense	7,718		7,718
Excess tax benefit of stock options exercised	14,549		14,549
Change in noncontrolling interest	(8,207)		(1,021)			(7,186)
Ending Balance at Jun. 30, 2011	$ 1,251,032	$ 860	$ 94,365	$ 1,128,713	$ (287)	$ 27,381
Ending Balance (in shares) at Jun. 30, 2011	86,047,759	86,048,000