Note 2 - Liquidity and Summary of Significant Accounting Principles - Anti-dilutive Securities Excluded From the Computation of Diluted Earnings (Loss) Per Share (Details) - shares	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Anti-dilutive securities (in shares)	4,439,167	4,626,667
Share-Based Payment Arrangement, Option [Member]
Anti-dilutive securities (in shares)	3,189,167	3,376,667
Warrant [Member]
Anti-dilutive securities (in shares)	450,000	450,000
Contingent Warrants Upon Future Financing Events [Member]
Anti-dilutive securities (in shares)	500,000	500,000
Performance Shares [Member]
Anti-dilutive securities (in shares)	300,000	300,000