Goodwill and Acquired Intangible Assets - Summary of Acquired Intangible Assets Subject to Amortization (Detail) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 4,513	$ 12,478
Accumulated Amortization	(932)	(4,085)
Net Book Value	3,581	8,393	[1]
Acquired Technology [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	3,753	11,718
Accumulated Amortization	(900)	(4,085)
Net Book Value	2,853	7,633
Customer Relationships [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	480	480
Accumulated Amortization	(20)	0
Net Book Value	460	480
Trade Name and Other [Member]
Finite Lived Intangible Assets [Line Items]
Gross Carrying Amount	280	280
Accumulated Amortization	(12)	0
Net Book Value	$ 268	$ 280

[1] The Condensed Consolidated Balance Sheet as of December 31, 2016 has been derived from the audited consolidated financial statements at that date but does not include all of the information and footnotes required by generally accepted accounting principles for complete financial statements.