Note 7 - Income Taxes (Details Textual) - USD ($)	3 Months Ended		12 Months Ended
	Dec. 31, 2017		Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			21.00%	34.00%	34.00%
Tax Adjustments, Settlements, and Unusual Provisions	$ 340,782
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability	$ 463,800	[1]	$ 401,000
Current Foreign Tax Expense (Benefit)			$ 0

[1] classified as part of the Federal deferred benefit in 2017