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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Property and Equipment - Schedule of Property and Equipment (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Dec. 31, 2021
Property, Plant and Equipment [Line Items]
Finance lease right-of-use asset	$ 13		$ 13		$ 13
Property and equipment at cost	3,199		3,199		3,477
Less: accumulated depreciation	(2,614)		(2,614)		(2,802)
Property and equipment, net	585		585		675
Depreciation	43	$ 53	87	$ 100
Equipment
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,111		$ 1,111		1,308
Equipment \| Minimum
Property, Plant and Equipment [Line Items]
Useful life (in years)			3 years
Equipment \| Maximum
Property, Plant and Equipment [Line Items]
Useful life (in years)			15 years
Tooling
Property, Plant and Equipment [Line Items]
Property and equipment, gross	414		$ 414		384
Tooling \| Minimum
Property, Plant and Equipment [Line Items]
Useful life (in years)			2 years
Tooling \| Maximum
Property, Plant and Equipment [Line Items]
Useful life (in years)			5 years
Vehicles
Property, Plant and Equipment [Line Items]
Property and equipment, gross	83		$ 83		83
Useful life (in years)			5 years
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property and equipment, gross	86		$ 86		86
Useful life (in years)			5 years
Computer software
Property, Plant and Equipment [Line Items]
Property and equipment, gross	1,144		$ 1,144		1,194
Useful life (in years)			3 years
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property and equipment, gross	142		$ 142		169
UV - Robots
Property, Plant and Equipment [Line Items]
Property and equipment, gross	105		$ 105		105
Useful life (in years)			5 years
Projects in progress
Property, Plant and Equipment [Line Items]
Property and equipment, gross	$ 101		$ 101		$ 135