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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The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

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Balance Sheet Components -Schedule of Property, Plant and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022	Dec. 31, 2022
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 9,806		$ 9,806		$ 9,788
Less: Accumulated depreciation	(8,857)		(8,857)		(8,724)
Property and equipment, net	949		949		1,064
Depreciation	100	$ 100	132	$ 213
Machinery, equipment, furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	4,452		4,452		4,434
Computer equipment and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,952		2,952		2,952
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,402		$ 2,402		$ 2,402