Balance Sheet Detail - Property and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2022	Jun. 30, 2022	Dec. 31, 2021
Balance Sheet Detail
Total property and equipment	$ 30	$ 30	$ 221
Less accumulated depreciation	(25)	(25)	(111)
Property and equipment, net	5	5	110
Loss on sale in other income	75	75
Research and development equipment
Balance Sheet Detail
Total property and equipment			158
Office equipment
Balance Sheet Detail
Total property and equipment	$ 30	$ 30	$ 63

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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- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

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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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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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