Note 12 - Derivative Financial Instruments (Details Textual) - USD ($)	6 Months Ended
	Jun. 30, 2021	Dec. 31, 2020	Mar. 31, 2019	Jun. 30, 2017
Derivative, Basis Spread on Variable Rate			1.45%
First Interest Rate Swap [Member]
Derivative, Notional Amount				$ 50,000,000
Derivative, Fixed Interest Rate				2.12%
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax, Parent, Total	$ (1,988,494)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, Tax, Parent, Total	(627,945)
Second Interest Rate Swap [Member]
Derivative, Notional Amount			$ 10,300,000
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification and Tax, Parent, Total	(643,690)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), after Reclassification, Tax, Parent, Total	(203,271)
Derivative, Variable Interest Rate			4.09%
Interest Rate Swap [Member]
Derivative, Notional Amount	$ 50,000,000
Derivative, Fixed Interest Rate	2.12%
Derivative, Collateral, Obligation to Return Cash	$ 3,800,000	$ 5,100,000