Foreign Currency Derivatives - Effect of Non-Designated Hedges in Condensed Consolidated Statements of Operations (Details) (Interest and other income (expense), net, USD $)
In Thousands, unless otherwise specified
3 Months Ended
Mar. 31, 2015
Mar. 31, 2014
Interest and other income (expense), net
   
Derivative Instruments Gain Loss [Line Items]    
Amount of Gain or (Loss) Recognized in Income on Derivative $ 4,673 $ 334