Derivative Instruments and Hedging Activities (Details 1) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Derivatives, Fair Value [Line Items]
Foreign Currency Derivative Instruments, Asset at Fair Value	$ 40,105	$ 36,574
Foreign Currency Derivative Instruments, Liability at Fair Value	$ (23,424)	$ (22,495)

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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- Definition

Fair value as of the balance sheet date of all foreign currency derivative assets not designated as hedging instruments.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624163-113959

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- Definition

Fair value as of the balance sheet date of all foreign currency derivative liabilities not designated as hedging instruments.

+ References

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