Note 12 - Fair Value Measurement - Fair Value Assumption Measurement of Warrant A (Details)	Dec. 31, 2022	Dec. 31, 2021	Sep. 30, 2021
Warrants and Rights Outstanding, Measurement Input	2.72	10.00	10.00
Measurement Input, Price Volatility [Member]
Warrants and Rights Outstanding, Measurement Input	92.2	69.5	71.0
Measurement Input, Risk Free Interest Rate [Member]
Warrants and Rights Outstanding, Measurement Input	0.043	0.008	0.004
Measurement Input, Expected Term [Member]
Warrants and Rights Outstanding, Measurement Input	4.0	4.8	5.0
Measurement Input, Expected Dividend Rate [Member]
Warrants and Rights Outstanding, Measurement Input	0	0	0