Note 4 - Warrants (Details Textual) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Mar. 31, 2024	Dec. 31, 2023
Share-Based Payment Arrangement, Expense	$ 453,000	$ 513,000	$ 946,000	$ 1,012,000
Equity Classified Warrants [Member]
Class of Warrant or Right, Number of Securities Called by Warrants or Rights (in shares)					3,334
Warrants and Rights Outstanding, Term (Year)					10 years
Class of Warrant or Right, Exercise Price of Warrants or Rights (in dollars per share)					$ 9.15
Class of Warrant or Right, Outstanding (in shares)	63,105		63,105			289,276
Class of Warrant or Right, Vested and Exercisable (in shares)	40,658		40,658			266,350
Share-Based Payment Arrangement, Expense	$ 35,000	$ 46,000	$ 68,000	$ 92,000
Share-based Payment Arrangement, Nonvested Award, Cost Not yet Recognized, Amount	$ 309,000		$ 309,000