Balance Sheet Detail - Property and Equipment (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Balance Sheet Detail
Total property and equipment	$ 221	$ 221
Less accumulated depreciation	(123)	(111)
Property and equipment, net	98	110
Research and development equipment
Balance Sheet Detail
Total property and equipment	158	158
Office equipment
Balance Sheet Detail
Total property and equipment	$ 63	$ 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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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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