Business Acquisitions Acquired Intangible Assets (Details) - USD ($) $ in Thousands		12 Months Ended
Apr. 30, 2014	Dec. 31, 2016
Business Acquisition [Line Items]
Useful Life (Years)		5 years
PECO and FGC Acquisitions
Business Acquisition [Line Items]
Amount	$ (5,158)
Useful Life (Years)	5 years 3 months 18 days
PECO and FGC Acquisitions \| Order backlog
Business Acquisition [Line Items]
Amount	$ (1,172)
Useful Life (Years)	1 year
PECO and FGC Acquisitions \| Trademarks
Business Acquisition [Line Items]
Amount	$ (90)
Useful Life (Years)	2 years
PECO and FGC Acquisitions \| Customer relationships
Business Acquisition [Line Items]
Amount	$ (870)
Useful Life (Years)	4 years
PECO and FGC Acquisitions \| Developed technology
Business Acquisition [Line Items]
Amount	$ (3,230)
Useful Life (Years)	7 years
PECO and FGC Acquisitions \| Net assumed contractual obligations
Business Acquisition [Line Items]
Amount	$ (204)
Useful Life (Years)	1 year

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275

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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

The amount of identifiable intangible assets recognized as of the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 55
-Paragraph 37
-URI http://asc.fasb.org/extlink&oid=73531372&loc=d3e2207-128464

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=73530397&loc=d3e4845-128472

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