Property and Equipment (Details) - Schedule of property and equipment - USD ($) $ in Thousands		9 Months Ended
		Sep. 30, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross		$ 2,427	$ 2,623
Less accumulated depreciation and amortization		(2,030)	(2,085)
Total		$ 397	538
Research and development equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life		5 years
Property, plant and equipment, gross		$ 1,425	1,397
Office and computer equipment [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	[1]	3 years
Property, plant and equipment, gross	[1]	$ 762	733
Autos [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life		5 years
Property, plant and equipment, gross		$ 54	54
Furniture and fixtures [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life		7 years
Property, plant and equipment, gross		$ 41	41
Leasehold improvements [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	[2]
Property, plant and equipment, gross		$ 113	283
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, gross		$ 32	$ 115

[1] In the three months ended and nine months ended September 30, 2021, the Company received net proceeds of less than $1 in the sale of research and development equipment resulting in gains on the sale of these assets of less than $1. In the three months ended and nine months ended September 30, 2020, the Company received net proceeds of $0 and $44 in the sale of research and development equipment and office and computer equipment, respectively, resulting in a gain on the sale of these assets of $0 and $18 for the three months ended and nine months ended September 30, 2020, respectively.

[2] Shorter of lease term or estimated useful life