Note 14 - Income Taxes - Reconciliation of Federal Income Tax Attributable to Operations to Income Tax Expense (Benefit) (Details) - USD ($)	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022
Statutory federal income tax benefit	$ (3,973,000)	$ (2,481,000)
Change in valuation allowance	3,779,000	(284,000)
Expiration of net operating losses	1,469,000	1,356,000
Disallowed financing costs	2,210,000	1,179,000
State and local taxes	(3,508,000)	200,000
Foreign rate differential		11,000
Other	$ 23,000	$ 19,000