Note 8 - Investments, Including Investments Accounted for Using the Equity Method - Reconciliation of the Company's Investments in Equity Affiliates (Details) - USD ($)	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Beginning of period			$ 952,128	$ 871,918	$ 871,918
Additional investments in unconsolidated affiliates			40,399		66,000
Distributions received			(668,788)		(59,550)
Loss on investment in affiliate			(105,664)
Equity in income of unconsolidated affiliates	$ 117,395	$ 48,513	502,486	$ 63,746	73,760
End of period	$ 720,561		$ 720,561		$ 952,128

Amount of gain (loss) on sale or disposal of an equity method investment.

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