Comprehensive Income (Details 2) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Accumulated Other Comprehensive Income [Roll Forward]
Foreign Currency Translation Adjustment, Beginning Balance	$ 45,905
Foreign Currency Translation Adjustment, Current Period Change	(3,511)	21,877	29,378
Foreign Currency Translation Adjustment, Ending Balance	42,394	45,905
Defined Benefit Plans, Beginning Balance	22
Defined Benefit Plans, Current Period Change	(42)	344	147
Defined Benefit Plans, Ending Balance	(20)	22
Net Unrealized Losses on Cash Flow Hedges, Beginning Balance	(5,813)
Net Unrealized Losses on Cash Flow Hedges, Current Period Change	1,334	(1,590)	3,991
Net Unrealized Losses on Cash Flow Hedges, Ending Balance	(4,479)	(5,813)
Accumulated Other Comprehensive Income, Beginning Balance	40,114
Accumulated Other Comprehensive Income, Current Period Change	(2,219)
Accumulated Other Comprehensive Income, Ending Balance	$ 37,895	$ 40,114