Goodwill and Intangible Assets, Net - Components of Intangible Assets (Detail) - USD ($) $ in Thousands	6 Months Ended	12 Months Ended
Jun. 30, 2018	Dec. 31, 2017
Finite Lived Intangible Assets [Line Items]
Gross	$ 3,194	$ 3,194
Accumulated Amortization	(2,342)	(2,236)
Net	$ 852	958
Weighted average remaining useful life	4 years
Trade Name [Member]
Finite Lived Intangible Assets [Line Items]
Gross	$ 3,194	3,194
Accumulated Amortization	(2,342)	(2,236)
Net	$ 852	$ 958
Weighted average remaining useful life	4 years	4 years 6 months

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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- Definition

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

+ References

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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

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

+ References

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- Definition

Remaining amortization period of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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