Balance Sheet Components - Schedule of Property and Equipment (Detail) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 147,243	$ 144,894
Less: accumulated depreciation	(118,191)	(111,247)
Property and equipment, net	29,052	33,647
Leasehold improvements [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	102,843	102,006
Laboratory Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	18,809	18,143
Machinery [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	8,234	8,312
Computer Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	9,262	9,545
Furniture and Fixtures [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	6,175	6,128
Construction in progress [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 1,920	$ 760

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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