Derivative Instruments, (Loss) Gain on Derivative Instruments (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Net (Loss) Gain on Derivative Instruments [Abstract]
Interest rate swap - change in fair value	$ (28)	$ 0	$ (39)	$ 0
Foreign exchange contracts- change in fair value	(14)	74	(178)	145
Remeasurement of related contract receivables, billings in excess of revenue earned, and subcontractor accruals	(17)	(3)	(89)	81
(Loss) gain on derivative instruments, net	$ (59)	$ 71	$ (306)	$ 226

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.

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- References

No definition available.

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- Definition

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

+ References

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (e)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959

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- Definition

Amount of gain (loss) included in earnings for the period from the increase (decrease) in fair value of interest rate derivatives not designated as hedging instruments.

+ References

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