Note 2 - Significant Accounting Policies (Details Textual) $ in Thousands, shares in Millions	12 Months Ended
Dec. 31, 2021 USD ($) shares	Dec. 31, 2020 USD ($) shares
Impairment of Long-Lived Assets Held-for-use	$ 0
Number of Operating Segments	1
Furniture and Fixtures [Member]
Property, Plant and Equipment, Useful Life (Year)	7 years
Office Equipment [Member]
Property, Plant and Equipment, Useful Life (Year)	5 years
Equipment [Member]
Property, Plant and Equipment, Useful Life (Year)	5 years
Vehicles [Member]
Property, Plant and Equipment, Useful Life (Year)	5 years
Mobile Facility [Member]
Property, Plant and Equipment, Useful Life (Year)	27 years 6 months
Building [Member]
Property, Plant and Equipment, Useful Life (Year)	39 years
Fair Value, Recurring [Member]
Assets, Fair Value Disclosure	$ 0	$ 0
Financial and Nonfinancial Liabilities, Fair Value Disclosure	$ 0	$ 0
Janssen [Member] \| Manufacturing Revenue [Member]
Treasury Stock, Shares, Acquired (in shares) \| shares	4.5	4.5

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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