Note 8 - Preferred Stock and Common Stock Warrants - Fair Value Assumptions (Details)	Mar. 31, 2022	Dec. 31, 2021
Measurement Input, Share Price [Member]
Warrant measurement input	6.62	2.85
Measurement Input, Exercise Price [Member]
Warrant measurement input	0.01	0.01
Measurement Input, Risk Free Interest Rate [Member]
Warrant measurement input	0.023	0.001
Measurement Input, Price Volatility [Member]
Warrant measurement input	0.596	0.626
Measurement Input, Expected Term [Member]
Warrant measurement input	1.6	1.6