Balance Sheet Components - Additional Information (Detail) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Depreciation	$ 1,521	$ 1,300	$ 1,238
Definite-lived intangible assets, net	11,308	6,542
Property, plant and equipment [Member]
Property, Plant and Equipment [Line Items]
Depreciation	2,300	2,000	1,800
Internally-developed software [Member]
Property, Plant and Equipment [Line Items]
Depreciation	300	200	$ 100
Definite-lived intangible assets, net	$ 1,700	$ 700