Note 11 - Income Taxes (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$ 1,026,000	$ (112,000)
Unrecognized Tax Benefits, Income Tax Penalties and Interest Expense	0	0
Research Tax Credit Carryforward [Member]
Tax Credit Carryforward, Amount	2,154,000	$ 2,154,000
Domestic Tax Jurisdiction [Member]
Operating Loss Carryforwards, Ownership Change	30,880,000
Operating Loss Carryforwards	143,636,000
Operating Loss Carryforwards, Expiring	75,224,000
State and Local Jurisdiction [Member]
Operating Loss Carryforwards	$ 106,323,000