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Balance Sheet Components - Property and Equipment, Net (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025	Dec. 31, 2025
Property and Equipment, net
Total property and equipment, gross	$ 26,580		$ 26,580		$ 26,178
Less: Accumulated depreciation and amortization	(9,733)		(9,733)		(7,988)
Total property and equipment, net	16,847		16,847		$ 18,190
Depreciation and amortization	$ 800	$ 900	$ 1,700	$ 1,700
Leasehold improvements
Property and Equipment, net
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Total property and equipment, gross	$ 18,018		$ 18,018		$ 17,655
Laboratory equipment
Property and Equipment, net
Estimated Useful Life (in years)	5 years		5 years		5 years
Total property and equipment, gross	$ 5,882		$ 5,882		$ 5,843
Furniture and fixtures
Property and Equipment, net
Estimated Useful Life (in years)	5 years		5 years		5 years
Total property and equipment, gross	$ 1,709		$ 1,709		$ 1,709
Computer equipment
Property and Equipment, net
Estimated Useful Life (in years)	5 years		5 years		5 years
Total property and equipment, gross	$ 896		$ 896		$ 896
Capitalized software
Property and Equipment, net
Estimated Useful Life (in years)	3 years		3 years		3 years
Total property and equipment, gross	$ 75		$ 75		$ 75