Accumulated Other Comprehensive (Loss) Income Accumulated Other Comprehensive (Loss) Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at balance sheet date	$ 1,824	$ 917
Other comprehensive (loss) income before reclassifications	(5,338)	1,572
Amounts reclassified from accumulated other comprehensive loss	(1,385)	(1,698)
Total changes in other comprehensive loss	(6,723)	(126)
Balance at balance sheet date	(4,899)	791
Foreign Currency Translation Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at balance sheet date	(2,080)	(971)
Other comprehensive (loss) income before reclassifications	(1,740)	(608)
Amounts reclassified from accumulated other comprehensive loss	0	0
Total changes in other comprehensive loss	(1,740)	(608)
Balance at balance sheet date	(3,820)	(1,579)
Unrealized Holding Gains (Losses) on Marketable Securities
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at balance sheet date	126	(123)
Other comprehensive (loss) income before reclassifications	229	176
Amounts reclassified from accumulated other comprehensive loss	0	0
Total changes in other comprehensive loss	229	176
Balance at balance sheet date	355	53
Unrealized Gains (Losses) on Foreign Currency Forward Contracts, net of tax
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance at balance sheet date	3,778	2,011
Other comprehensive (loss) income before reclassifications	(3,827)	2,004
Amounts reclassified from accumulated other comprehensive loss	(1,385)	(1,698)
Total changes in other comprehensive loss	(5,212)	306
Balance at balance sheet date	$ (1,434)	$ 2,317