Derivative Instruments, Gain (Loss) On Derivative Instruments (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Derivative, Gain (Loss) on Derivative, Net [Abstract]
Foreign exchange contracts- change in fair value	$ (118)	$ (86)
Remeasurement of related contract receivables, billings in excess of revenue earned, and subcontractor accruals	(38)	(74)
(Loss) gain on derivative instruments, net	$ (156)	$ (160)

Amount of gain (loss) recognized in earnings in the period due to Gain (loss) on remeasurement of related contract receivables, billings in excess of revenue earned, and subcontractor accruals.

No definition available.

+ Details

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- References

No definition available.

+ Details

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- Definition

Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959

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- Definition

Amount of gain (loss) recognized in earnings in the period from the increase (decrease) in fair value of foreign currency derivatives 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 4C
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959

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