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Leases - Additional Information (Details) - USD ($) $ in Thousands | 1 Months Ended | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | --- | ---
Jan. 31, 2026 | Nov. 30, 2025 | Jun. 30, 2026 | Mar. 31, 2026 | Jun. 30, 2026 | Dec. 31, 2026 | Dec. 31, 2025
Operating Leased Assets [Line Items] |  |  |  |  |  |  |  |
Restricted cash - current assets |  |  | $ 917 |  | $ 917 |  | $ 0 | [1]
Restricted cash - non-current assets |  |  | 610 |  | 610 |  | 1,527 | [1]
Right of use assets |  |  | 5,037 |  | 5,037 |  | 3,396 | [1]
2016 Lease [Member] |  |  |  |  |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |  |  |  |  |
Lease liabilities |  |  | 1,400 |  | 1,400 |  | 4,200 |
Variable lease cost |  |  | 700 |  | 1,400 |  |  |
Right of use assets |  |  | 1,100 |  | 1,100 |  | 3,400 |
2026 Lease Operating Lease |  |  |  |  |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |  |  |  |  |
Lease liabilities |  |  | 4,261 |  | 4,261 |  |  |
Right of use assets |  |  | 3,905 |  | 3,905 |  |  |
Tenant improvement allowance |  |  | 356 |  | 356 |  |  |
Letter of Credit | 2016 Lease [Member] |  |  |  |  |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |  |  |  |  |
Letter of credit outstanding, amount |  |  | 900 |  | 900 |  |  |
Restricted cash - current assets |  |  | 900 |  | 900 |  |  |
Restricted cash - non-current assets |  |  |  |  |  |  | $ 900 |
Lease rent expense |  |  | $ 1,200 |  | $ 2,200 |  |  |
New Lease Agreement |  |  |  |  |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |  |  |  |  |
Sublease Income | $ 600 |  |  |  |  |  |  |
Offset against operating lease cost |  |  |  | $ 200 |  |  |  |
New Lease Agreement | 2016 Lease [Member] |  |  |  |  |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |  |  |  |  |
Lease term description |  |  |  |  | The 2016 Lease has an initial term of ten years through September 2026 and the Company had an option to extend the initial term for an additional five years at the then fair rental value as determined pursuant to the 2016 Lease. |  |  |
Initial lease term |  |  | 10 years |  | 10 years |  |  |
Extended lease term |  |  | 5 years |  | 5 years |  |  |
New Lease Agreement | 2026 Lease Operating Lease |  |  |  |  |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |  |  |  |  |
Lease term description |  |  |  |  | In November 2025, the Company entered into a lease (the “2026 Lease”) of office and laboratory space located in Emeryville, California for the Company’s corporate headquarters. The contractual term for the 2026 Lease is October 1, 2026 to December 31, 2029. The Company determined that the lease commencement date for accounting purposes is April 1, 2026, when the office and laboratory space is available for use by the Company to begin construction of its leasehold improvements, and resulted in recognition of approximately $4.1 million lease liabilities and the related right of use assets. The Company expects to utilize the full amount of the one-time tenant improvement allowance of $0.4 million receivable from landlord. The Company has two options to extend the term, each for an additional two years, at the then fair market rent as determined under the term of the 2026 Lease. In addition, the Company has provided a security deposit of $0.5 million or letter of credit with anticipated reduction to $0.3 million at the end of December 2026, which may be drawn by the Landlord to be applied for certain purposes upon the Company’s breach of any provisions under the 2026 Lease. The Company has recorded the $0.5 million Letter of Credit as non-current restricted cash on its balance sheet as of June 30, 2026 and December 31, 2025. |  |  |
Lease rent expense |  |  |  |  | $ 400 |  |  |
Lease liabilities |  |  | $ 4,100 |  | 4,100 |  |  |
Right of use assets |  |  | 4,100 |  | 4,100 |  |  |
Tenant improvement allowance |  |  | 400 |  | $ 400 |  |  |
Lease commencement date |  | Oct. 01, 2026 |  |  |  |  |  |
Lease expiration date |  | Dec. 31, 2029 |  |  |  |  |  |
Operating lease, option to extend |  |  |  |  | The Company has two options to extend the term, each for an additional two years, at the then fair market rent as determined under the term of the 2026 Lease. |  |  |
Operating lease, existence of option to terminate |  |  |  |  | true |  |  |
New Lease Agreement | Letter of Credit | 2026 Lease Operating Lease |  |  |  |  |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |  |  |  |  |
Restricted cash - non-current assets |  |  | 500 |  | $ 500 |  |  |
Operating lease security deposit |  |  | $ 500 |  | $ 500 |  |  |
New Lease Agreement | Letter of Credit | 2026 Lease Operating Lease | Forecast |  |  |  |  |  |  |  |
Operating Leased Assets [Line Items] |  |  |  |  |  |  |  |
Operating lease security deposit |  |  |  |  |  | $ 300 |  |
[1] | The condensed balance sheet as of December 31, 2025 was derived from the audited financial statements included in the Company's Annual Report on Form 10-K for the year ended December 31, 2025.

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