CONDENSED STATEMENTS OF SHAREHOLDERS' EQUITY (UNAUDITED) - USD ($)	Common Stock [Member]	Additional Paid-In Capital [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Total
Balance, beginning at Dec. 31, 2016	$ 8,738	$ 52,824,950	$ 14,781,018	$ (9,000)	$ 67,605,706
Balance, beginning (in shares) at Dec. 31, 2016	8,739,836
Net income			2,014,948		2,014,948
Change in unrealized loss from interest rate swap				4,200	4,200
Stock-based compensation expense	$ 95	696,910			697,005
Stock-based compensation expense (in shares)	92,813
Balance, ending at Jun. 30, 2017	$ 8,833	53,521,860	16,795,966	(4,800)	70,321,859
Balance, ending (in shares) at Jun. 30, 2017	8,832,649
Balance, beginning at Dec. 31, 2017	$ 8,863	53,770,618	20,548,652	(14,800)	$ 74,313,333
Balance, beginning (in shares) at Dec. 31, 2017	8,864,319				8,864,319
Net income			2,513,990		$ 2,513,990
Change in unrealized loss from interest rate swap				$ 14,800	14,800
Common stock issued as employee compensation	$ 5	45,908			45,913
Common stock issued as employee compensation (in shares)	5,130
Stock-based compensation expense	$ 67	459,649			459,716
Stock-based compensation expense (in shares)	69,042
Balance, ending at Jun. 30, 2018	$ 8,935	$ 54,276,175	$ 23,062,642		$ 77,347,752
Balance, ending (in shares) at Jun. 30, 2018	8,938,491				8,938,491