Note 11 - Income Taxes (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent	21.00%	21.00%
Valuation Allowance, Deferred Tax Asset, Increase (Decrease), Amount	$ 2,081,649	$ 2,473,248
Operating Loss Carryforwards, Expired	800,000
Domestic Tax Authority [Member]
Operating Loss Carryforwards, Total	8,200,000
Domestic Tax Authority [Member] | Internal Revenue Service (IRS) [Member]
Operating Loss Carryforwards, Total	4,200,000
Tax Credit Carryforward, Amount	600,000
Tax Credit Carryforward, Expired	0
Foreign Tax Authority [Member]
Operating Loss Carryforwards, Total	$ 3,500,000