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Related-party Transactions - Narrative (Details) ft² in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2022 USD ($)	Dec. 31, 2022 USD ($)	Sep. 30, 2021 USD ($) ft²
Related Party Transaction [Line Items]
Accrued liabilities and other current liabilities	$ 29,652		$ 29,652		$ 28,755
Other non-current liabilities	3,776		3,776		4,113
Related Party
Related Party Transaction [Line Items]
Rentable area \| ft²						18
Related Party \| Sonoma
Related Party Transaction [Line Items]
Rentable area \| ft²						18
Tenant improvements						$ 4,600
Accrued liabilities and other current liabilities	500		500		500
Other non-current liabilities	3,100		3,100		3,500
Related Party \| GSK
Related Party Transaction [Line Items]
Contract liabilities	0		0		$ 0
Revenue recognized	$ 0	$ 0	$ 0	$ 36,300
Related Party \| Minimum \| Lyell Immunopharma \| GSK
Related Party Transaction [Line Items]
Ownership interest (as a percent)	10.00%		10.00%