Balance Sheet Components - Schedule of Deferred Revenue (Detail) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Deferred Revenue [Line Items]
Total deferred revenue	$ 5,623	$ 7,361
Total deferred revenue	5,623	7,361
Less: current portion of deferred revenue	(5,249)	(7,361)
Deferred revenue, net of current portion	374
Product
Deferred Revenue [Line Items]
Total deferred revenue	5,050	6,919
Total deferred revenue	5,050	6,919
Services
Deferred Revenue [Line Items]
Total deferred revenue	573	442
Total deferred revenue	$ 573	$ 442