Note 9 - Income Taxes - Effective Income Tax Rate Reconciliation (Details) - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Expected provision at federal statutory tax rate (21%)	$ (1,031,888)	$ (1,167,092)
Provision for valuation allowance	2,497,414
Foreign tax loss	57,856	99,215
Adjustment to 2017 tax return		58,304
State taxes, net of federal benefit	(11,506)	80,367
Stock-based compensation expense		185,675
Federal research & development credit	(174,416)	(83,245)
Other permanent differences	76,448	470,214
Income tax expense/(benefit)	$ 1,413,908	$ (356,562)

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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