Note 10 - Stockholders' Equity - Outstanding Warrants (Details)	Dec. 31, 2022 $ / shares shares
Outstanding Warrants to Purchase Shares (in shares)	21,515
The 2018 Warrants [Member]
Outstanding Warrants to Purchase Shares (in shares)	6,490
Exercise Price (in dollars per share) | $ / shares	$ 1.00
The 2020 Warrants [Member]
Outstanding Warrants to Purchase Shares (in shares)	4,500
Exercise Price (in dollars per share) | $ / shares	$ 1.055
The January 2021 Warrants [Member]
Outstanding Warrants to Purchase Shares (in shares)	10,525
Exercise Price (in dollars per share) | $ / shares	$ 2.88