Derivative and Hedging Activities - Balance Sheet Location (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Derivative [Line Items]
Foreign Currency Derivative Instruments Not Designated as Hedging Instruments, Asset at Fair Value	$ 0	$ 33
Foreign Currency Derivative Instruments Not Designated as Hedging Instruments, Liability at Fair Value	333	4
Prepaid Expenses and Other Current Assets [Member] \| Not Designated as Hedging Instrument [Member] \| Foreign Exchange Forward [Member]
Derivative [Line Items]
Foreign Currency Derivative Instruments Not Designated as Hedging Instruments, Asset at Fair Value	0	33
Accrued Liabilities [Member] \| Not Designated as Hedging Instrument [Member] \| Foreign Exchange Forward [Member]
Derivative [Line Items]
Foreign Currency Derivative Instruments Not Designated as Hedging Instruments, Liability at Fair Value	$ 333	$ 4

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=109980867&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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