Note 1 - Organization and Significant Accounting Policies - Weighted Average Assumptions (Details)	Dec. 31, 2020	Dec. 31, 2019
Measurement Input, Risk Free Interest Rate [Member]
Warrants and right, measurement input	0.001	0.019
Measurement Input, Expected Dividend Rate [Member]
Warrants and right, measurement input	0.000	0.000
Measurement Input, Expected Term [Member]
Warrants and right, measurement input	0.2	1.7
Measurement Input, Price Volatility [Member]
Warrants and right, measurement input	0.568	0.703