CONDENSED BALANCE SHEETS [Parenthetical] - USD ($)	Jun. 30, 2016	Dec. 31, 2015
Allowance for doubtful accounts	$ 41,373	$ 58,684
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	$ 7,695,144	$ 6,642,501
Preferred stock, par value (in dollars per share)	$ 0.005	$ 0.005
Preferred stock, shares authorized	872,521	872,521
Preferred stock, shares issued	0	0
Preferred stock, shares outstanding	0	0
Common stock, par value (in dollars per share)	$ 0.005	$ 0.005
Common stock, shares authorized	50,000,000	50,000,000
Common stock, shares issued	6,127,850	6,090,671
Treasury stock, shares	668,130	668,130