Derivative Instruments And Hedging Activities - Derivative Instruments Designated As Hedging Instruments (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Asset derivative instruments designated as hedging instruments	$ 1,064	$ 966
Liability derivative instruments designated as hedging instruments	6,211	12,467
Other Current Assets | Interest Rate Swaps
Derivatives, Fair Value [Line Items]
Asset derivative instruments designated as hedging instruments	863	311
Other Assets, Net | Interest Rate Swaps
Derivatives, Fair Value [Line Items]
Asset derivative instruments designated as hedging instruments	201	655
Accrued Liabilities | Foreign Exchange Contracts
Derivatives, Fair Value [Line Items]
Liability derivative instruments designated as hedging instruments	5,857	7,492
Other Non-Current Liabilities | Foreign Exchange Contracts
Derivatives, Fair Value [Line Items]
Liability derivative instruments designated as hedging instruments	$ 354	$ 4,975