Note 9 - Stockholders' Equity - Summary of Warrants Outstanding (Details)	Sep. 30, 2023 $ / shares shares
Securities into which warrants are convertible (in shares)	227,434
First Set of Warrants Expiring September 2024 [Member]
Securities into which warrants are convertible (in shares)	44,148
Securities into which warrants are convertible (in dollars per share) | $ / shares	$ 1.1
First Set of Warrants Expiring April 2024 [Member]
Securities into which warrants are convertible (in shares)	26,515
Securities into which warrants are convertible (in dollars per share) | $ / shares	$ 1.375
Second Set of Warrants Expiring April 2024 [Member]
Securities into which warrants are convertible (in shares)	29,150
Securities into which warrants are convertible (in dollars per share) | $ / shares	$ 2.5
Warrants Expiring March 2025 [Member]
Securities into which warrants are convertible (in shares)	100,532
Securities into which warrants are convertible (in dollars per share) | $ / shares	$ 3.125
Warrants Expiring February 2025 [Member]
Securities into which warrants are convertible (in shares)	16,175
Securities into which warrants are convertible (in dollars per share) | $ / shares	$ 3.125
Warrants Expiring March 2024 [Member]
Securities into which warrants are convertible (in shares)	10,914
Securities into which warrants are convertible (in dollars per share) | $ / shares	$ 22.99