Summary of Significant Accounting Policies - Net Income (Loss) per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Net Income	$ 254	$ 2,250	$ 1,756	$ 4,168
Weighted-average common shares outstanding (basic) (in shares)	5,779	5,676	5,753	5,656
Effect of dilutive securities:
Weighted-average common shares outstanding (diluted) (in shares)	6,006	5,807	5,960	5,768
Net income per share
Net income per share – basic (in dollars per share)	$ 0.04	$ 0.40	$ 0.31	$ 0.74
Net income per share – diluted (in dollars per share)	$ 0.04	$ 0.39	$ 0.29	$ 0.72
Anti-dilutive weighted-average common shares excluded from calculation of diluted earnings per share (in shares)	184	306	206	200
Restricted shares
Effect of dilutive securities:
Restricted and performance shares (in shares)	146	115	145	106
Performance shares
Effect of dilutive securities:
Restricted and performance shares (in shares)	81	16	62	6