Consolidated Statements of Comprehensive Income (Unaudited) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Consolidated Statements of Comprehensive Income (Unaudited) [Abstract]
Net Income	$ 54,176	$ 46,798	$ 162,412	$ 103,807
Other Comprehensive Income (Loss), Net of Tax [Abstract]
Foreign currency translation adjustment	1,372	(8,027)	2,640	(3,490)
Net unrealized gains/(losses) on foreign currency cash flow hedges	(544)	(2,289)	1,416	(2,144)
Less: Reclassification adjustment for realized losses (gains) in current earnings	(78)	419	52	315
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	750	(9,897)	4,108	(5,319)
Comprehensive Income	$ 54,926	$ 36,901	$ 166,520	$ 98,488