Goodwill and Intangible Assets - Summary of Intangible Assets (Detail) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016
Goodwill [Line Items]
Gross Value	$ 18,308	$ 17,393
Accumulated Amortization	(13,647)	(10,126)
Net Value	4,661	7,267
Customer Relationships [Member]
Goodwill [Line Items]
Gross Value	7,474	6,899
Accumulated Amortization	(4,283)	(3,208)
Net Value	3,191	3,691
Developed Technology [Member]
Goodwill [Line Items]
Gross Value	5,524	5,184
Accumulated Amortization	(4,663)	(3,801)
Net Value	861	1,383
Intellectual Property [Member]
Goodwill [Line Items]
Gross Value	2,340	2,340
Accumulated Amortization	(2,262)	(2,129)
Net Value	78	211
Supply Agreement [Member]
Goodwill [Line Items]
Gross Value	1,400	1,400
Accumulated Amortization	(1,400)	(544)
Net Value		856
License [Member]
Goodwill [Line Items]
Gross Value	500	500
Accumulated Amortization	(500)	(113)
Net Value		387
Patent [Member]
Goodwill [Line Items]
Gross Value	500	500
Accumulated Amortization	(89)	(20)
Net Value	411	480
Trade Names [Member]
Goodwill [Line Items]
Gross Value	370	370
Accumulated Amortization	(335)	(285)
Net Value	35	85
Non-compete [Member]
Goodwill [Line Items]
Gross Value	200	200
Accumulated Amortization	(115)	(26)
Net Value	$ 85	$ 174

Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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