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Related-party Transactions (Details) ft² in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2023 USD ($)	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)	Sep. 30, 2021 USD ($) ft²
Related Party Transaction [Line Items]
Revenue recognized from related parties	$ 0
Affiliated Entity \| Sublease with Sonoma
Related Party Transaction [Line Items]
Rentable area \| ft²				18
Tenant improvements				$ 4,600
Due to related parties, current	500		$ 500
Due to related parties, noncurrent	3,400		3,500
Revenue recognized from related parties	700	$ 700
Sublease income	500	500
Investor \| GSK Agreement
Related Party Transaction [Line Items]
Due to related parties, current	0		$ 0
Revenue recognized from related parties	$ 0	$ 600
Investor \| GSK Agreement \| Minimum \| Lyell Immunopharma \| GSK
Related Party Transaction [Line Items]
Ownership interest (as a percent)	10.00%