Accounting Policies - Fair Value (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Fair Values of Financial Instruments
Foreign exchange hedges assets		$ 111
Foreign exchange hedges liabilities	$ (35)
Recurring \| Fair value \| Cash flows approach
Fair Values of Financial Instruments
Foreign exchange hedges assets		111
Foreign exchange hedges liabilities	(35)
Recurring \| Fair value \| Significant Other Observable Inputs (Level 2) \| Cash flows approach
Fair Values of Financial Instruments
Foreign exchange hedges assets		$ 111
Foreign exchange hedges liabilities	$ (35)

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No definition available.

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959

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- Definition

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+ References

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