Derivatives Fair Value Derivatives, Balance Sheet Location (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Derivatives, Fair Value [Line Items]
Foreign Currency Cash Flow Hedge Asset at Fair Value	$ 97
Foreign Currency Cash Flow Hedge Liability at Fair Value	839
Cash Flow Hedge \| Interest Rate Swap \| Other Assets [Member]
Derivatives, Fair Value [Line Items]
Foreign Currency Cash Flow Hedge Liability at Fair Value	693	$ 751
Cash Flow Hedge \| Interest Rate Swap \| Designated as Hedging Instrument \| Other Current Assets
Derivatives, Fair Value [Line Items]
Foreign Currency Cash Flow Hedge Liability at Fair Value	278	2
Cash Flow Hedge \| Foreign currency hedges \| Other Current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Foreign Currency Cash Flow Hedge Liability at Fair Value	$ 742	$ 601

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- Definition

Fair value as of the balance sheet date of all foreign currency derivative assets designated as cash flow 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)(1)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959

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Fair value as of the balance sheet date of all foreign currency derivative liabilities designated as cash flow hedging instruments.

+ References

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