Derivative Financial Instruments Settled Foreign Currency Exchange Rate Risk (Details) $ in Thousands	12 Months Ended
Dec. 31, 2018 USD ($) $ / $
Foreign Currency Forward [Member]
Derivatives [Line Items]
Foreign Currency Cash Flow Hedge Gain (Loss) Reclassified to Earnings, Net	$ 800
Foreign Currency Forward 1 [Member]
Derivatives [Line Items]
Effective Date	Apr. 18, 2018
Maturity Date	Jul. 05, 2018
Notional Amount	$ 5,379
Derivative, Forward Exchange Rate \| $ / $	0.78
Foreign Currency Forward 2 [Member]
Derivatives [Line Items]
Effective Date	May 02, 2018
Maturity Date	Nov. 05, 2018
Notional Amount	$ 4,315
Derivative, Forward Exchange Rate \| $ / $	0.75
Foreign Currency Forward 3 [Member]
Derivatives [Line Items]
Effective Date	May 02, 2018
Maturity Date	Dec. 21, 2018
Notional Amount	$ 5,753
Derivative, Forward Exchange Rate \| $ / $	0.75

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
-Sentence Column B

+ Details

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- Definition

Contractual rate at which a foreign currency can be purchased or sold.

+ References

No definition available.

+ Details

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- Definition

Date the entity entered into the derivative contract, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

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.

+ References

No definition available.

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- Definition

Date the derivative contract matures, in CCYY-MM-DD format.

+ References

No definition available.

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- Definition

The amount of net gains or losses on foreign currency cash flow hedges reclassified during the period to earnings from accumulated other comprehensive income upon the hedged transaction affecting earnings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959

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