Note 9 - Income Taxes (Details Textual) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Net Income (Loss) Attributable to Parent, Total	$ (138,009)	$ (2,502,802)	$ (3,707,685)	$ (3,274,924)
CVD Tantaline ApS [Member] | DENMARK
Net Income (Loss) Attributable to Parent, Total			149,000	513,000
Deferred Tax Assets, Gross, Total	$ 33,000	$ 113,000	$ 33,000	$ 113,000
CVD Tantaline ApS [Member] | DENMARK | Foreign Tax Authority [Member] | The Danish Ministry of Taxation [Member]
Effective Income Tax Rate Reconciliation, at Foreign Statutory Income Tax Rate, Percent	22.00%		22.00%