Note 9 - Fair Value Measurements - Financial Instruments Measured at Fair Value (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021	Dec. 01, 2021
Outstanding warrants (in shares)	450,000	233,333
Stock Purchase Warrants 4 [Member]
Issue date fair value			$ 163,096
Outstanding warrants (in shares)			3,977,961
Stock Purchase Warrants 6 [Member]
Issue date fair value			$ 13,937
Outstanding warrants (in shares)			2,877,500