Balance Sheet Components - Schedule of Property and Equipment (Detail) - USD ($)	Dec. 31, 2024	Dec. 31, 2023
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 0	$ 117,742,000
Less: accumulated depreciation	0	(112,957,000)
Property and equipment, net	0	4,785,000
Leasehold improvements [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	0	84,920,000
Laboratory Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	0	20,589,000
Computer Equipment [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	0	6,510,000
Furniture and Fixtures [Member]
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 0	$ 5,723,000

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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