Property and Equipment (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 1,099	$ 1,029
Less accumulated depreciation	(874)	(798)
Net property and equipment	225	231
Leasehold improvements
Property, Plant and Equipment [Line Items]
Property, Plant and Equipment, Gross	$ 463	463
Leasehold improvements | Minimum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	2 years
Leasehold improvements | Maximum [Member]
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	5 years
Computer and office equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	3 years
Property, Plant and Equipment, Gross	$ 83	60
Furniture and fixtures
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	7 years
Property, Plant and Equipment, Gross	$ 93	46
Scientific equipment
Property, Plant and Equipment [Line Items]
Property, plant and equipment, useful life	7 years
Property, Plant and Equipment, Gross	$ 460	$ 460