Note 1 - Organization and Significant Accounting Policies - Weighted Average Assumptions (Details)	Dec. 31, 2019	Dec. 31, 2018
Measurement Input, Risk Free Interest Rate [Member]
Warrants and right, measurement input	0.019	0.026
Measurement Input, Expected Dividend Rate [Member]
Warrants and right, measurement input	0	0
Measurement Input, Expected Term [Member]
Warrants and right, measurement input	0.017	0.028
Measurement Input, Price Volatility [Member]
Warrants and right, measurement input	0.703	0.634