Note 6 - Stock Warrants - Summary of Warrants (Details) - $ / shares	9 Months Ended
	Sep. 30, 2022	Mar. 15, 2021
Number of shares (in shares)	1,402,417	534,067
Exercise price (in dollars per share)	$ 17.43
Remaining contractual life (Year)	3 years 2 months 4 days
Warrant One [Member]
Number of shares (in shares)	12,833
Exercise price (in dollars per share)	$ 75.00
Remaining contractual life (Year)	3 months 29 days
Warrant Two [Member]
Number of shares (in shares)	431,250
Exercise price (in dollars per share)	$ 10.00
Remaining contractual life (Year)	2 years 3 months 29 days
Warrant Three [Member]
Number of shares (in shares)	958,334
Exercise price (in dollars per share)	$ 20.00
Remaining contractual life (Year)	3 years 7 months 6 days