Balance Sheet Components - Summary of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 3,884	$ 3,686
Less: Accumulated depreciation	(2,339)	(2,106)
Property and equipment, net	1,545	1,580
Tools and Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	2,043	1,991
Computer Equipment and Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	37	37
Furniture and Fixtures
Property Plant And Equipment [Line Items]
Property and equipment, gross	461	402
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	38	38
Construction In Process
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 1,305	$ 1,218

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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