Goodwill and Intangible Assets - Schedule of Intangible Assets (Detail) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Dec. 31, 2016
Finite Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 14,670	$ 14,670
Less: accumulated amortization	(9,496)	(7,345)
Intangible assets, net	$ 5,174	7,325	[1]
Minimum [Member]
Finite Lived Intangible Assets [Line Items]
Intangible assets amortized useful lives	2 years
Maximum [Member]
Finite Lived Intangible Assets [Line Items]
Intangible assets amortized useful lives	6 years
Developed technology [Member]
Finite Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 9,910	9,910
Developed technology [Member] | Minimum [Member]
Finite Lived Intangible Assets [Line Items]
Intangible assets amortized useful lives	5 years
Developed technology [Member] | Maximum [Member]
Finite Lived Intangible Assets [Line Items]
Intangible assets amortized useful lives	6 years
Customer relationships [Member]
Finite Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 3,370	3,370
Intangible assets amortized useful lives	4 years
Non-compete agreements and tradename [Member]
Finite Lived Intangible Assets [Line Items]
Intangible assets, gross	$ 1,390	$ 1,390
Non-compete agreements and tradename [Member] | Minimum [Member]
Finite Lived Intangible Assets [Line Items]
Intangible assets amortized useful lives	2 years
Non-compete agreements and tradename [Member] | Maximum [Member]
Finite Lived Intangible Assets [Line Items]
Intangible assets amortized useful lives	3 years

[1] Derived from our audited consolidated financial statements as of December 31, 2016.