Facility Leases - Lease Cost (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Burlingame Lease
Operating lease cost
Total operating lease cost	$ 1,744	$ 1,644	$ 1,402
Other Information
Operating cash flows used for operating lease	$ 1,892	$ 1,839	$ 1,695
Remaining lease term	1 month 6 days	1 year 1 month 6 days	2 years 1 month 6 days
Discount rate	8.00%	8.00%	8.00%
South San Francisco Lease
Operating lease cost
Total operating lease cost	$ 46
Other Information
Operating cash flows used for operating lease	$ 153
Remaining lease term	3 years
Discount rate	11.70%
Research and Development | Burlingame Lease
Operating lease cost
Operating lease costs	$ 1,273	$ 1,224	$ 1,051
Costs of non-lease components (previously common area maintenance)	471	$ 420	$ 351
Research and Development | South San Francisco Lease
Operating lease cost
Operating lease costs	$ 46