BALANCE SHEET COMPONENTS - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 54,958	$ 53,600
Less: accumulated depreciation and amortization	(34,601)	(33,358)
Property and equipment, net	20,357	20,242
Prototype
Property, Plant and Equipment [Line Items]
Property and equipment, gross	17,730	17,730
Machinery and equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	17,701	17,701
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	14,088	14,088
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,295	1,295
Software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,389	1,389
Construction in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,755	$ 1,397

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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