Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - 3 months ended Mar. 31, 2018 - USD ($)	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]	AOCI Attributable to Parent [Member]	Total
Balance at Dec. 31, 2017	$ 687,850	$ 50,856,069	$ (37,125,541)	$ 60,679,308	$ (206,193)	$ 74,891,493
Net income				1,355,745		1,355,745
Other comprehensive income (loss)					(26,942)	(26,942)
Dividends on common stock ($0.12 per share)				(532,771)		(532,771)
Stock award plans		(35,357)	158,592			123,235
Stock options exercised	450	23,330				23,780
Balance at Mar. 31, 2018	$ 688,300	$ 50,844,042	$ (36,966,949)	$ 61,502,282	$ (233,135)	$ 75,834,540

Amount of increase to additional paid-in capital (APIC) from recognition of equity-based compensation.

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