Note 8 - Derivative Financial Instruments (Details Textual) - USD ($)	1 Months Ended	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax		$ 227,642		$ 227,642
Interest Rate Swap [Member]
Derivative, Notional Amount	$ 50,000,000	$ 50,000,000		$ 50,000,000
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, before Tax	143,415
Other Comprehensive Income (Loss), Unrealized Gain (Loss) on Derivatives Arising During Period, Tax	$ 84,228