Financial Instruments (Fair Value Of Derivative Instruments On Consolidated Balance Sheets) (Details) - Not Designated As Hedging Instrument [Member] - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Other Non-current Assets [Member] | Interest Rate Swaps [Member]
Derivatives, Fair Value [Line Items]
Asset derivatives		$ 1,616
Other Non-current Assets [Member] | Cross Currency Swaps [Member]
Derivatives, Fair Value [Line Items]
Asset derivatives	$ 3,043
Other Current Assets [Member] | Cross Currency Swaps [Member]
Derivatives, Fair Value [Line Items]
Asset derivatives	8,980
Other Current Assets [Member] | Foreign Currency Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Asset derivatives	3,640	661
Accrued Expenses And Other Current Liabilities [Member] | Interest Rate Swaps [Member]
Derivatives, Fair Value [Line Items]
Liability derivatives	(1,243)	(124)
Accrued Expenses And Other Current Liabilities [Member] | Foreign Currency Forward Contracts [Member]
Derivatives, Fair Value [Line Items]
Liability derivatives	(780)	$ (1,130)
Other Non-current Liabilities [Member] | Interest Rate Swaps [Member]
Derivatives, Fair Value [Line Items]
Liability derivatives	(367)
Other Non-current Liabilities [Member] | Cross Currency Swaps [Member]
Derivatives, Fair Value [Line Items]
Liability derivatives	$ (1,203)