Derivatives - Balance Sheet Location (Details) - USD ($)
$ in Thousands
Dec. 31, 2016
Dec. 31, 2015
Other Current Assets    
Derivatives, Fair Value [Line Items]    
Assets $ 2,754 $ 4,143
Other Current Assets | Foreign exchange forward | Designated as Hedging Instrument    
Derivatives, Fair Value [Line Items]    
Assets 2,535 3,626
Other Current Assets | Foreign exchange forward | Not Designated as Hedging Instrument    
Derivatives, Fair Value [Line Items]    
Assets 219 517
Accrued Expenses    
Derivatives, Fair Value [Line Items]    
Liabilities 1,783 2,014
Accrued Expenses | Foreign exchange forward | Designated as Hedging Instrument    
Derivatives, Fair Value [Line Items]    
Liabilities 1,759 1,443
Accrued Expenses | Foreign exchange forward | Not Designated as Hedging Instrument    
Derivatives, Fair Value [Line Items]    
Liabilities $ 24 $ 571