Note 3 - Property, Plant, and Equipment (Details Textual) - USD ($)	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Property, Plant and Equipment, Gross, Ending Balance	$ 14,420,559	$ 19,055,260
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Ending Balance	9,722,009	13,378,021
Depreciation, Total	584,457	$ 674,141
Disposal Group, Held-for-sale, Not Discontinued Operations [Member]
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment, Current	560,000
Property, Plant and Equipment, Gross, Ending Balance	4,700,000
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment, Ending Balance	$ 4,140,000