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Leases - Narrative (Details) ft² in Thousands, $ in Thousands | 3 Months Ended | 6 Months Ended |  |  |
--- | --- | --- | --- | --- | ---
Jun. 30, 2023 USD ($) | Jun. 30, 2022 USD ($) | Jun. 30, 2023 USD ($) | Jun. 30, 2022 USD ($) | Dec. 31, 2022 | Sep. 30, 2021 USD ($) ft² | May 31, 2021 ft²
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |
Operating lease cost | $ 2,300 | $ 2,200 | $ 4,400 | $ 4,700 |  |  |
Variable lease cost | $ 1,400 | 1,200 | $ 2,800 | 2,500 |  |  |
Weighted average remaining lease term of operating leases | 7 years 3 months 18 days |  | 7 years 3 months 18 days |  | 7 years 9 months 18 days |  |
Operating lease, weighted average discount rate (as a percent) | 8.50% |  | 8.50% |  | 8.50% |  |
South San Francisco, California |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |
Rentable area | ft² |  |  |  |  |  |  | 11
Sublease income | $ 200 | 200 | $ 400 | 400 |  |  |
Related Party |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |
Rentable area | ft² |  |  |  |  |  | 18 |
Related Party | Sonoma |  |  |  |  |  |  |
Lessee, Lease, Description [Line Items] |  |  |  |  |  |  |
Rentable area | ft² |  |  |  |  |  | 18 |
Sublease income | $ 464 | $ 466 | $ 930 | $ 931 |  |  |
Tenant improvements |  |  |  |  |  | $ 4,600 |

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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 55 -Paragraph 53 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479589/842-20-55-53 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 842 -SubTopic 20 -Name Accounting Standards Codification -Section 50 -Paragraph 4 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147478964/842-20-50-4 + Details
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