CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Cumulative-effect adjustment for adoption of ASC 842	Common Stock	Treasury Stock	Additional Paid-In Capital	Accumulated Deficit	Accumulated Deficit Cumulative-effect adjustment for adoption of ASC 842
Beginning Balance (shares) at Sep. 30, 2018			11,899	0
Beginning Balance at Sep. 30, 2018	$ 39,418		$ 12	$ 0	$ 84,285	$ (44,879)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Expense related to director restricted stock unit (shares)			102
Expense related to director restricted stock unit	527				527
Expense related to employee stock options	263				263
Exercise of stock options (shares)			35
Exercise of stock options	39				39
Net income	$ 5,324					5,324
Ending Balance (shares) at Sep. 30, 2019	12,036		12,036	0
Ending Balance at Sep. 30, 2019	$ 45,571	$ (2)	$ 12	$ 0	85,114	(39,555)	$ (2)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Expense related to director restricted stock unit (shares)			90
Expense related to director restricted stock unit	347				347
Expense related to employee stock options	$ 563				563
Exercise of stock options (shares)	395		395
Exercise of stock options	$ 55				55
Repurchases of common stock (in shares)				28
Repurchases of common stock	(113)			$ (113)
Cancellation of common stock (in shares)			(117)	(28)
Cancellation of common stock	(98)			$ 113	(211)
Net income	$ 7,114					7,114
Ending Balance (shares) at Sep. 30, 2020	12,404		12,404	0
Ending Balance at Sep. 30, 2020	$ 53,437		$ 12	$ 0	$ 85,868	$ (32,443)