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Leases - Additional Information (Detail) $ in Thousands |  | 1 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Jun. 30, 2018 ft² | Oct. 31, 2023 ft² | Feb. 28, 2023 ft² | Nov. 30, 2021 ft² | Dec. 31, 2020 ft² | Oct. 31, 2020 USD ($) ft² | May 31, 2019 ft² | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2019 USD ($) | May 31, 2022 ft²
Lessee Lease Description [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Tenant improvement allowance | $ |  |  |  |  |  |  |  |  |  |  | $ 15,700 |
Amount form letter of credit | $ |  |  |  |  |  |  |  | $ 1,546 | $ 1,472 |  |  |
Lease expiration year |  |  |  |  |  |  |  | 2029 |  |  |  |
Operating lease, renewal period |  |  |  |  |  |  |  | 10 years |  |  |  |
Operating lease term |  |  |  |  |  |  |  | The lease expires in 2029 with an option to renew for a period of ten years. |  |  |  |
Weighted average remaining lease term for operating leases |  |  |  |  |  |  |  | 5 years 2 months 12 days |  |  |  |
Weighted average discount rate for operating leases |  |  |  |  |  |  |  | 8.50% |  |  |  |
Cash paid for amounts included In measurement of lease liabilities | $ |  |  |  |  |  |  |  | $ 8,400 | $ 8,200 | $ 7,900 |  |
Offices and Laboratory Facilities | South San Francisco |  |  |  |  |  |  |  |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Area under lease | ft² | 105,000 |  |  |  | 23,600 |  |  |  |  |  |  |
Area under sublease | ft² |  |  | 9,300 | 7,100 |  |  | 25,000 |  |  |  |  |
Sublease expiration month and year |  | 2024-11 | 2025-02 |  |  |  |  |  | 2022-12 | 2021-11 |  |
Additional area sublease expiration month and year |  |  |  |  |  |  |  | 2023-11 |  |  |  |
Operating sublease, existence of option to extend |  |  |  |  |  |  |  |  | true |  |  |
Additional area of property in lease | ft² |  | 13,250 |  |  |  |  |  |  |  |  |  | 13,150
Offices and Laboratory Facilities | South San Francisco |  |  |  |  |  |  |  |  |  |  |  |
Lessee Lease Description [Line Items] |  |  |  |  |  |  |  |  |  |  |  |
Tenant improvement allowance | $ |  |  |  |  |  | $ 400 |  |  |  |  |  |
Area of property | ft² |  |  |  |  |  | 18,700 |  |  |  |  |  |
Lease, description |  |  |  |  |  |  |  | In October 2020, the Company signed a lease agreement to lease approximately 18,700 square feet of office and laboratory space in Newark, California. The lease term ends on February 6, 2028 with an option to extend for an additional five years. The landlord is obligated to pay for up to $0.4 million of tenant improvements. |  |  |  |
Lease expiration date |  |  |  |  |  | Feb. 06, 2028 |  |  |  |  |  |
Extend for an additional lease term |  |  |  |  |  | 5 years |  |  |  |  |  |

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