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Balance Sheet Components - Summary of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 41,138	$ 39,265
Less accumulated depreciation and amortization	(10,957)	(5,413)
Total property and equipment, net	30,181	33,852
Lab Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	11,610	10,458
Computer Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,764	1,554
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	25,542	25,222
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 2,222	$ 2,031

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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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