Note 11 - Common Stock - Assumptions (Details) - Warrant [Member]	Jan. 19, 2021	Jan. 18, 2021
Measurement Input, Exercise Price [Member] | Series B Warrants [Member]
Warrants and Rights Outstanding, Measurement Input	3.40	6.10
Measurement Input, Exercise Price [Member] | Series A-2 and Series B-2 Warrants [Member]
Warrants and Rights Outstanding, Measurement Input	3.40	6.37
Measurement Input, Share Price [Member] | Series B Warrants [Member]
Warrants and Rights Outstanding, Measurement Input	3.19	3.19
Measurement Input, Share Price [Member] | Series A-2 and Series B-2 Warrants [Member]
Warrants and Rights Outstanding, Measurement Input	3.19	3.19
Measurement Input, Expected Term [Member] | Series B Warrants [Member]
Warrants and Rights Outstanding, Measurement Input	3.9	3.9
Measurement Input, Expected Term [Member] | Series A-2 and Series B-2 Warrants [Member]
Warrants and Rights Outstanding, Measurement Input	4.3	4.3
Measurement Input, Price Volatility [Member] | Series B Warrants [Member]
Warrants and Rights Outstanding, Measurement Input	0.90	0.90
Measurement Input, Price Volatility [Member] | Series A-2 and Series B-2 Warrants [Member]
Warrants and Rights Outstanding, Measurement Input	0.90	0.90
Measurement Input, Risk Free Interest Rate [Member] | Series B Warrants [Member]
Warrants and Rights Outstanding, Measurement Input	0.0033	0.0033
Measurement Input, Risk Free Interest Rate [Member] | Series A-2 and Series B-2 Warrants [Member]
Warrants and Rights Outstanding, Measurement Input	0.0033	0.0033
Measurement Input, Expected Dividend Rate [Member] | Series B Warrants [Member]
Warrants and Rights Outstanding, Measurement Input	0	0
Measurement Input, Expected Dividend Rate [Member] | Series A-2 and Series B-2 Warrants [Member]
Warrants and Rights Outstanding, Measurement Input	0	0