Balance Sheet Components - Summary of Property and Equipment, Net (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 3,423	$ 3,267
Less: Accumulated depreciation	(1,975)	(1,627)
Property and equipment, net	1,448	1,640
Tools and Equipment
Property Plant And Equipment [Line Items]
Property and equipment, gross	1,991	2,010
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	286	323
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	$ 1,071	$ 859

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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