Note 4 - Earnings Per Share - Basic and Diluted Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Dec. 31, 2018	Dec. 31, 2017
Net income	$ 2,197	$ 5,181
Weighted average number of shares of common stock outstanding (in shares)	22,386,566	22,359,828
Effect of dilutive securities (in shares)	209,395	6,921
Weighted average number of shares of common stock outstanding including effect of dilutive securities (in shares)	22,595,961	22,366,749
Basic earnings per share (in dollars per share)	$ 0.10	$ 0.23
Diluted earnings per share (in dollars per share)	$ 0.10	$ 0.23