Note 12 - Net Income Per Share - Computation of Basic and Diluted Per Share Data (Details) - USD ($)	3 Months Ended
	Dec. 31, 2019	Dec. 31, 2018
Net Income	$ 1,045,000	$ 1,275,000
Basic earnings per common share (in dollars per share)	$ 0.16	$ 0.19
Diluted earnings per common share (in dollars per share)	$ 0.16	$ 0.19
Basic (in shares)	6,567,765	6,685,415
Incremental Common Shares Attributable to Share-based Payment Arrangements, Total	68,333	307
Diluted (in shares)	6,636,098	6,685,722