Balance Sheet Components - Property and Equipment, Net (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 10,659	$ 7,068
Less: Accumulated depreciation and amortization	(5,635)	(4,111)
Property and equipment, net	6,969	3,724
Depreciation	1,700	1,100	$ 1,000
Lab Equipment, Tooling and Molds [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	3,228	2,766
Computer Software [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,019	1,337
Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,757	1,366
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,670	1,070
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	950	494
Vehicles [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	35	35
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 1,945	767
Scenario, Previously Reported [Member] | Computer Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, gross		$ 400