Balance Sheet Components - Property and Equipment, Net (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 5,417	$ 5,322
Less accumulated depreciation and amortization	(1,507)	(1,239)
Total	3,910	4,083
Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	5,348	5,253
Office Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 69	$ 69

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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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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