Note 9 - Income Taxes - Effective Income Tax Rate Reconciliation (Details) - USD ($)	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Income tax provision at federal statutory rate (21%)	$ (552,918)	$ 169,296
Foreign tax loss	16,673	9,855
State taxes	3,000	9,000
Difference between tax and book depreciation	24,072	33,037
Stock compensation	25,002	44,860
Other Permanent differences	28,171	(18,278)
Income tax expense (benefit) provision	$ (456,000)	$ 247,770

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

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