Foreign Currency Derivatives - Effect of Derivative Instruments Designated as Cash Flow Hedges in Condensed Consolidated Statements of Operations (Details) (USD $)
In Thousands, unless otherwise specified
 3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Derivative Instruments Gain Loss [Line Items]    
Foreign exchange contracts, Gain or (loss) recognized in OCI-effective portion, total $ 6,298 $ (421)
Gain or (loss) reclassified from OCI into income- effective portion, total 2,558 (666)
Gain or (Loss) Recognized-Ineffective Portion and Amount Excluded from Effectiveness Testing (31) [1] 75 [1]
Product revenues    
Derivative Instruments Gain Loss [Line Items]    
Gain or (loss) reclassified from OCI into income- effective portion, total 6,636 (2,865)
Cost of revenues    
Derivative Instruments Gain Loss [Line Items]    
Gain or (loss) reclassified from OCI into income- effective portion, total (801) 532
Sales and marketing    
Derivative Instruments Gain Loss [Line Items]    
Gain or (loss) reclassified from OCI into income- effective portion, total (1,787) 1,080
Research and development    
Derivative Instruments Gain Loss [Line Items]    
Gain or (loss) reclassified from OCI into income- effective portion, total (715) 415
General and administrative    
Derivative Instruments Gain Loss [Line Items]    
Gain or (loss) reclassified from OCI into income- effective portion, total (775) 172
Interest and other income (expense), net    
Derivative Instruments Gain Loss [Line Items]    
Gain or (Loss) Recognized-Ineffective Portion and Amount Excluded from Effectiveness Testing (31) [1] 75 [1]
Foreign exchange contract    
Derivative Instruments Gain Loss [Line Items]    
Foreign exchange contracts, Gain or (loss) recognized in OCI-effective portion, total $ 6,298 $ (421)
[1] There were no gains or losses recognized in income due to ineffectiveness in the periods presented.