STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($)	Total	Common Stock [Member]	Additional Paid-in Capital [Member]	Treasury Stock [Member]	Retained Earnings [Member]
BALANCE at Dec. 31, 2012	$ 11,222,669	$ 29,703	$ 28,460,764	$ (10,081,789)	$ (7,186,009)
BALANCE (in shares) at Dec. 31, 2012		5,940,558		668,130
Shares issued - vested	0	$ 185	(185)	$ 0	0
Shares issued - vested (in shares)		36,988		0
Exercise of stock options	20,839	$ 22	20,817	$ 0	0
Exercise of stock options (in shares)		4,350		0
Tax withholding related to vested shares from employee stock plans	(154,522)	$ 0	(154,522)	$ 0	0
Stock compensation expense	538,304	0	538,304	0	0
Excess tax benefit from stock-based compensation plans	23,534	0	23,534	0	0
Cash dividends declared	(3,178,909)	0	0	0	(3,178,909)
Net income	3,805,210	0	0	0	3,805,210
BALANCE at Dec. 31, 2013	12,277,125	$ 29,910	28,888,712	$ (10,081,789)	(6,559,708)
BALANCE (in shares) at Dec. 31, 2013		5,981,896		668,130
Shares issued - vested	0	$ 260	(260)	$ 0	0
Shares issued - vested (in shares)		52,046		0
Exercise of stock options	32,768	$ 46	32,722	$ 0	0
Exercise of stock options (in shares)		9,249		0
Tax withholding related to vested shares from employee stock plans	(147,378)	$ 0	(147,378)	$ 0	0
Stock compensation expense	608,645	0	608,645	0	0
Excess tax benefit from stock-based compensation plans	71,582	0	71,582	0	0
Cash dividends declared	(3,212,267)	0	0	0	(3,212,267)
Net income	3,206,081	0	0	0	3,206,081
BALANCE at Dec. 31, 2014	12,836,556	$ 30,216	29,454,023	$ (10,081,789)	(6,565,894)
BALANCE (in shares) at Dec. 31, 2014		6,043,191		668,130
Shares issued - vested	0	$ 199	(199)	$ 0	0
Shares issued - vested (in shares)		39,814		0
Exercise of stock options	60,432	$ 38	60,394	$ 0	0
Exercise of stock options (in shares)		7,666		0
Tax withholding related to vested shares from employee stock plans	(226,612)	$ 0	(226,612)	$ 0	0
Stock compensation expense	673,855	0	673,855	0	0
Excess tax benefit from stock-based compensation plans	60,143	0	60,143	0	0
Cash dividends declared	(3,242,020)	0	0	0	(3,242,020)
Net income	1,511,176	0	0	0	1,511,176
BALANCE at Dec. 31, 2015	$ 11,673,530	$ 30,453	$ 30,021,604	$ (10,081,789)	$ (8,296,738)
BALANCE (in shares) at Dec. 31, 2015		6,090,671		668,130