Note 9 - Derivatives (Details Textual) - USD ($)	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Agent Warrants In Connection With March 2020 Private Placement [Member]
Derivative Liability, Total	$ 13		$ 135
Derivative, Gain (Loss) on Derivative, Net, Total	122	$ 419
Agent Warrants Issued in Connection with May 2020 Offering [Member]
Derivative Liability, Total	58		333
Derivative, Gain (Loss) on Derivative, Net, Total	275	335
Agent Warrants In Connection With June 2020 Warrant [Member]
Derivative Liability, Total	296		$ 908
Derivative, Gain (Loss) on Derivative, Net, Total	$ 612	$ 199