Consolidated Statements of Operations - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Income Statement [Abstract]
Net sales	$ 7,548,100	$ 6,211,100	$ 21,755,700	$ 17,428,900
Operating costs and expenses:
Cost of sales	4,284,600	3,495,300	12,042,600	9,761,900
Advertising	528,600	61,100	1,087,900	460,300
Selling	1,336,600	1,198,100	4,043,600	3,513,300
General and administrative	733,200	770,200	2,433,900	2,182,600
Total operating costs and expenses	6,883,000	5,524,700	19,608,000	15,918,100
Income from operations	665,100	686,400	2,147,700	1,510,800
Other income	6,800	31,200	16,100	43,400
Interest expense	(7,400)	(7,300)	(22,000)	(21,800)
Income before income taxes	664,500	710,300	2,141,800	1,532,400
Income tax (expense) benefit	(191,500)	(4,600)	2,377,500	(20,400)
Net income	$ 473,000	$ 705,700	$ 4,519,300	$ 1,512,000
Net income per common share
Basic	$ 0.04	$ 0.06	$ 0.39	$ 0.13
Diluted	$ 0.04	$ 0.06	$ 0.38	$ 0.13
Weighted average shares outstanding:
Basic	11,665,461	11,537,066	11,617,562	11,495,122
Diluted	11,927,877	11,840,758	11,907,486	11,785,515