Balance Sheet Components - Schedule of Property Plant and Equipment (Detail) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 2,538	$ 296
Accumulated depreciation	(41)	(9)
Property, plant and equipment, net	2,497	287
Computer Equipment
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	242	95
Laboratory Equipment
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	407
Construction in Progress
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 1,889	$ 201

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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