Note 1 - Summary of Significant Accounting Policies (Details Textual) - USD ($)	3 Months Ended	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			21.00%
Other Comprehensive Income (Loss) Taxes			$ 343,316	$ 771,697
Geographic Concentration Risk [Member] \| Revenue from Contract with Customer Benchmark [Member] \| ILLINOIS
Concentration Risk, Percentage	22.70%	22.30%	25.00%	25.80%

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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