Statements of Earnings - USD ($)	12 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2014
Net sales	$ 75,287,726	$ 60,323,917	$ 58,045,292
Cost of sales	42,417,478	35,455,964	33,446,526
Gross profit	32,870,248	24,867,953	24,598,766
Operating expenses
Selling, general and administrative	22,138,556	17,816,598	16,080,640
Income from operations	10,731,692	7,051,355	8,518,126
Interest income	157,402	105,891	95,703
Income before income taxes	10,889,094	7,157,246	8,613,829
Income tax expense	2,876,032	2,475,238	3,180,978
Net income	$ 8,013,062	$ 4,682,008	$ 5,432,851
Basic (in dollars per share)	$ 0.60	$ 0.35	$ 0.42
Diluted (in dollars per share)	$ 0.59	$ 0.34	$ 0.40
Basic (in shares)	13,372,579	13,216,010	12,916,273
Diluted (in shares)	13,663,349	13,587,532	13,601,594