Derivatives - Fair Value of Derivative Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Designated as hedging instrument | Interest rate swap | Other assets (long-term)
Derivatives, Fair Value [Line Items]
Total Asset Derivatives	$ 4,321	$ 5,772
Designated as hedging instrument | Foreign currency forward contracts | Other assets (long-term)
Derivatives, Fair Value [Line Items]
Total Asset Derivatives	162	151
Designated as hedging instrument | Foreign currency forward contracts | Prepaid expenses and other assets
Derivatives, Fair Value [Line Items]
Total Asset Derivatives	636	613
Designated as hedging instrument | Foreign currency forward contracts | Accrued expenses
Derivatives, Fair Value [Line Items]
Total Liability Derivatives	(1,458)	(711)
Designated as hedging instrument | Foreign currency forward contracts | Other long-term obligations
Derivatives, Fair Value [Line Items]
Total Liability Derivatives	(194)	(101)
Not designated as hedging instrument | Foreign currency forward contracts | Prepaid expenses and other assets
Derivatives, Fair Value [Line Items]
Total Asset Derivatives	633	814
Not designated as hedging instrument | Foreign currency forward contracts | Accrued expenses
Derivatives, Fair Value [Line Items]
Total Liability Derivatives	$ (405)	$ (796)