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Leases - Narrative (Details) ft² in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2024 USD ($)	Mar. 31, 2023 USD ($)	Dec. 31, 2023	Sep. 30, 2021 USD ($) ft²	May 31, 2021 ft²
Lessee, Lease, Description [Line Items]
Operating lease cost	$ 2,300	$ 2,100
Variable lease cost	$ 2,300	1,400
Weighted average remaining lease term of operating leases	6 years 7 months 6 days		6 years 9 months 18 days
Operating lease, weighted average discount rate (as a percent)	8.50%		8.50%
South San Francisco, California
Lessee, Lease, Description [Line Items]
Rentable area (in square feet) | ft²					11
Sublease income	$ 200	200
Related Party
Lessee, Lease, Description [Line Items]
Rentable area (in square feet) | ft²				18
Related Party | Sonoma
Lessee, Lease, Description [Line Items]
Rentable area (in square feet) | ft²				18
Sublease income	$ 465	$ 465
Tenant improvements				$ 4,600

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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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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Carrying amount as of the balance sheet date of improvements having a life longer than one year that were made for the benefit of one or more tenants.

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Amount of variable lease cost, excluded from lease liability, recognized when obligation for payment is incurred for finance and operating leases.

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