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Manufacturing agreement initial term.

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Number of leased buildings.

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Number of options to extend lease term.

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Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount before accumulated depreciation of additions or improvements to assets held under a lease arrangement.

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Description of terms and conditions of option to extend lessee's operating lease. Includes, but is not limited to, information about option recognized as part of right-of-use asset and lease liability.

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Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Commitments and Contingencies - Additional Information (Details) $ in Thousands	1 Months Ended			3 Months Ended	12 Months Ended
	Aug. 31, 2020	Jun. 30, 2020 ft² Options Building	Apr. 30, 2020 m²	Mar. 31, 2025 USD ($)	Dec. 31, 2027 USD ($)	Dec. 31, 2026 USD ($)	Dec. 31, 2025 USD ($)	Dec. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)	Jan. 31, 2023 USD ($)
Commitments And Contingencies Disclosure [Line Items]
Operating lease right-of-use asset							$ 36,606	$ 46,508
Lease liabilities							59,180
Non Cash Lease Impairment Expense				$ 1,900
Sublease income							(4,622)	0	$ 0
Variable sublease income							1,400
Payment for sublease					$ 500	$ 5,700
Variable lease expenses							3,250	3,320	3,618
Current portion of tenant improvement allowance payable							20,607	11,030
Operating Lease, Cost							12,245	12,988	13,192
Lonza
Commitments And Contingencies Disclosure [Line Items]
Leasehold improvements and machinery and equipment										$ 81,700
Lonza \| Service Agreements
Commitments And Contingencies Disclosure [Line Items]
Cancelable and/ or non-cancelable contractual obligations, total							23,900
Unrecorded unconditional purchase obligation, expenses recognized							34,800	$ 25,800	$ 59,700
Clinical and Commercial Supply of Drug Substance \| Manufacturing Agreement \| Lonza
Commitments And Contingencies Disclosure [Line Items]
Unrecorded unconditional purchase obligation, expenses recognized							$ 86,500
Clinical and Commercial Supply of Drug Substance \| Maximum \| Manufacturing Agreement \| Lonza
Commitments And Contingencies Disclosure [Line Items]
Manufacturing agreement initial term	8 years
Manufacturing agreement term that can be extended	16 years
Lease Agreement on June 2020 \| Maximum
Commitments And Contingencies Disclosure [Line Items]
Lease area \| ft²		83,000
Lease Agreement on June 2020 \| Minimum
Commitments And Contingencies Disclosure [Line Items]
Lease area \| ft²		73,000
Lease Agreement on June 2020 \| California
Commitments And Contingencies Disclosure [Line Items]
Number of buildings leased \| Building		2
Initial lease term		6 years 6 months
Lease Agreement on June 2020 \| 1200 Page Mill Road in Palo Alto \| California
Commitments And Contingencies Disclosure [Line Items]
Lessee operating lease option to extend		6.5 years
Lease Agreement on June 2020 \| 1250 Page Mill Road in Palo Alto \| California
Commitments And Contingencies Disclosure [Line Items]
Initial lease term		13 years
Lessee operating lease option to extend		five
Number of options to extend lease term \| Options		2
Lease Agreement on April 2020 \| Rottenstrasse 5 in Visp \| Switzerland
Commitments And Contingencies Disclosure [Line Items]
Lease area \| m²			1,000
Initial lease term			5 years
Automatic renewal interval			5 years
Lease Agreement on April 2020 \| Rottenstrasse 5 in Visp \| Switzerland \| Maximum
Commitments And Contingencies Disclosure [Line Items]
Lessee, operating lease, term of contract			15 years