Derivative Instruments And Hedging Activities - Derivative Instruments Designated As Hedging Instruments (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Asset derivative instruments designated as hedging instruments	$ 1,502	$ 966
Liability derivative instruments designated as hedging instruments	9,223	12,467
Other Current Assets \| Interest Rate Swaps
Derivatives, Fair Value [Line Items]
Asset derivative instruments designated as hedging instruments	670	311
Other Assets, Net \| Interest Rate Swaps
Derivatives, Fair Value [Line Items]
Asset derivative instruments designated as hedging instruments	832	655
Accrued Liabilities \| Foreign Exchange Contracts
Derivatives, Fair Value [Line Items]
Liability derivative instruments designated as hedging instruments	6,396	7,492
Other Noncurrent Liabilities \| Foreign Exchange Contracts
Derivatives, Fair Value [Line Items]
Liability derivative instruments designated as hedging instruments	$ 2,827	$ 4,975

Aggregate fair value of all derivative assets designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 10
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77997519&loc=d3e13433-108611

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Aggregate fair value of all derivative liabilities designated as hedging instruments. Includes instruments designated as cash flow hedges, fair value hedges, and hedges of net investments in foreign operations.

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