Note 2 - Basis of Presentation and Significant Accounting Policies - Estimated Useful Lives of Property, Plant and Equipment (Details)	12 Months Ended
	Dec. 31, 2021
Land Improvements [Member]
Estimated useful lives (Year)	12 years
Building [Member] | Maximum [Member]
Estimated useful lives (Year)	40 years
Plant and Equipment [Member] | Maximum [Member]
Estimated useful lives (Year)	12 years
Plant and Equipment [Member] | Minimum [Member]
Estimated useful lives (Year)	2 years