Balance Sheet Components - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 53,600	$ 52,563
Less: accumulated depreciation and amortization	(33,358)	(28,501)
Property and equipment, net	20,242	24,062
Prototype
Property Plant And Equipment [Line Items]
Property and equipment, gross	17,730	17,711
Machine and equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	17,701	17,486
Leasehold improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	14,088	14,196
Furniture and fixture
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	$ 1,397	$ 486

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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