Balance Sheet Components - Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 9,788	$ 9,060
Less: Accumulated depreciation	(8,724)	(8,457)
Property and equipment, net	1,064	603
Depreciation	267	296
Machinery, equipment, furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	4,434	3,742
Computer equipment and software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	2,952	2,916
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 2,402	$ 2,402

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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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