Balance Sheet Components - Components of Property and Equipment - Net (Details) - USD ($) $ in Thousands	Jun. 30, 2024	Dec. 31, 2023
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 2,765	$ 2,889
Less: accumulated depreciation	(2,361)	(2,367)
Total property and equipment, net	404	522
Machinery, Computer Equipment and Software
Property Plant And Equipment [Line Items]
Property and equipment, gross	2,633	2,759
Leasehold Improvements
Property Plant And Equipment [Line Items]
Property and equipment, gross	94	94
Furniture
Property Plant And Equipment [Line Items]
Property and equipment, gross	$ 38	$ 36

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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