Note 9 - Earnings Per Common Share - Summary of Earnings Per Share Calculation (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017
Net Income	$ 1,497,079	$ 567,439	$ 2,265,456	$ 1,722,102
Weighted average shares of common stock outstanding - Basic (in shares)	2,720,654	2,888,502	2,826,347	2,882,278
Earnings Per Share - Basic (in dollars per share)	$ 0.55	$ 0.20	$ 0.80	$ 0.60
Warrants, Options and Convertible Notes (in shares)	371,866	273,473	360,599	218,738
Weighted average shares of common stock -Diluted (in shares)	3,092,520	3,161,975	3,186,946	3,101,016
Earnings Per Share - Diluted (in dollars per share)	$ 0.48	$ 0.18	$ 0.71	$ 0.56