Condensed Consolidated Statements of Shareholders' Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Treasury Stock	Accumulated other comprehensive income	Accumulated deficit
Beginning balance (in shares) at Sep. 30, 2020		29,551
Shares of common stock
Stock-based compensation (in shares)		230
Stock option exercises (in shares)		2
Ending balance (in shares) at Dec. 31, 2020		29,783
Balance, beginning of period at Sep. 30, 2020		$ 744,361	$ (47,721)	$ 918	$ (623,409)
Shares of common stock
Stock-based compensation		903
Stock option exercises		7
Tax withholding paid on behalf of employees for stock-based awards		(83)
Translation adjustment	$ (10)			(10)
Net income	2,569				2,569
Balance, end of period at Dec. 31, 2020	$ 77,535	$ 745,188	(47,721)	908	(620,840)
Beginning balance (in shares) at Sep. 30, 2021	36,984	36,984
Shares of common stock
Stock-based compensation (in shares)		285
Stock option exercises (in shares)		6
Ending balance (in shares) at Dec. 31, 2021	37,275	37,275
Balance, beginning of period at Sep. 30, 2021		$ 782,266	(47,721)	687	(597,766)
Shares of common stock
Stock-based compensation		1,088
Stock option exercises		29
Tax withholding paid on behalf of employees for stock-based awards		(54)
Translation adjustment	$ 20			20
Net income	2,414				2,414
Balance, end of period at Dec. 31, 2021	$ 140,963	$ 783,329	$ (47,721)	$ 707	$ (595,352)