Note 2 - Net Income Per Share - Net Income Per Common Share (Details) - USD ($)	3 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Net income	$ 1,383,320	$ 1,069,373
Weighted average common shares (in shares)	13,288,679	13,222,180
Dilutive potential common shares (in shares)	286,483	359,254
Weighted average dilutive common shares outstanding (in shares)	13,575,162	13,581,434
Net income per common share:
Basic (in dollars per share)	$ 0.10	$ 0.08
Diluted (in dollars per share)	$ 0.10	$ 0.08