Balance Sheet Components - Schedule of Property, Plant and Equipment (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 40,845	$ 296
Accumulated depreciation	(292)	(9)
Property, plant and equipment, net	40,553	287
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	1,876
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	759
Computer Equipment
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	818	95
Laboratory Equipment
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	476
Construction in Progress
Property Plant And Equipment [Line Items]
Property, plant and equipment, gross	$ 36,916	$ 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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