STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($)	Common Stock [Member]	Additional Paid-in Capital [Member]	Accumulated Deficit [Member]	Total
Balance at Dec. 31, 2015	$ 107,223	$ 29,279,791	$ (25,076,973)	$ 4,310,041
Balance (in shares) at Dec. 31, 2015	10,722,321
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 0	0	52,443	52,443
Cash dividend paid	0	0	(536,120)	(536,120)
Exercise of stock options	$ 1	(1)	0	0
Exercise of stock options (in shares)	80
Stock-based compensation	$ 0	139,673	0	139,673
Balance at Dec. 31, 2016	$ 107,224	29,419,463	(25,560,650)	$ 3,966,037
Balance (in shares) at Dec. 31, 2016	10,722,401			10,722,401
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	$ 0	0	12,070	$ 12,070
Cash dividend paid	0	0	(536,120)	(536,120)
Stock-based compensation	0	140,321	0	140,321
Balance at Dec. 31, 2017	$ 107,224	$ 29,559,784	$ (26,084,700)	$ 3,582,308
Balance (in shares) at Dec. 31, 2017	10,722,401			10,722,401