Balance Sheet Components - Schedule of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Less: accumulated amortization and depreciation	$ (530)	$ (283)
Property and equipment, net	500	709
Computer Equipment
Property Plant And Equipment [Line Items]
Property and equipment	33	28
Lab Equipment
Property Plant And Equipment [Line Items]
Property and equipment	405	405
Finance Lease Right of Use Assets
Property Plant And Equipment [Line Items]
Property and equipment	556	$ 559
Leasehold Improvement
Property Plant And Equipment [Line Items]
Property and equipment	21
Office Furniture
Property Plant And Equipment [Line Items]
Property and equipment	$ 15

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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