Intangible Assets - Schedule of Intangible Assets (Detail) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Finite and Indefinite Lived Intangible Assets [Line Items]
Intangible assets, Trade name	$ 2,507	$ 2,696
Intangible assets, gross	13,117	13,668
Accumulated amortization	(3,554)	(2,647)
Intangible assets, net	9,563	11,021
Customer Relationships [Member]
Finite and Indefinite Lived Intangible Assets [Line Items]
Intangible assets, gross	6,271	6,543
Developed Technology [Member]
Finite and Indefinite Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 4,339	$ 4,429