Business Acquisition - Unaudited Pro forma Financial Information (Details) - Evolv Inc. - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Business Acquisition [Line Items]
Revenue	$ 268,771	$ 190,551
Net loss	$ (85,521)	$ (64,474)

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=56956515&loc=d3e1392-128463

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration