Property, Plant and Equipment, Net (Details) - USD ($) $ in Thousands	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 2,614	$ 2,614
Less: accumulated depreciation	(2,504)	(2,397)
Property, plant and equipment, net	110	217
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	584	584
Furniture, machinery and equipment [Member]
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	1,553	1,553
Computer equipment and software [Member]
Property, Plant and Equipment [Line Items]
Total property, plant and equipment	$ 477	$ 477