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, 2021		36,984
Shares of common stock
Stock-based compensation (in shares)		405
Stock option exercises (in shares)		6
Sale of common stock (in shares)		0
Ending balance (in shares) at Mar. 31, 2022		37,395
Balance, beginning of period at Sep. 30, 2021		$ 782,266	$ (47,721)	$ 687	$ (597,766)
Shares of common stock
Stock-based compensation		2,232
Stock option exercises		29
Tax withholding paid on behalf of employees for stock-based awards		(156)
Sale of common stock		0
Translation adjustment	$ 22			22
Net (loss) income	189				189
Balance, end of period at Mar. 31, 2022	139,782	$ 784,371	(47,721)	709	(597,577)
Beginning balance (in shares) at Dec. 31, 2021		37,275
Shares of common stock
Stock-based compensation (in shares)		120
Stock option exercises (in shares)		0
Sale of common stock (in shares)		0
Ending balance (in shares) at Mar. 31, 2022		37,395
Balance, beginning of period at Dec. 31, 2021		$ 783,329	(47,721)	707	(595,352)
Shares of common stock
Stock-based compensation		1,144
Stock option exercises		0
Tax withholding paid on behalf of employees for stock-based awards		(102)
Sale of common stock		0
Translation adjustment	2			2
Net (loss) income	(2,225)				(2,225)
Balance, end of period at Mar. 31, 2022	$ 139,782	$ 784,371	(47,721)	709	(597,577)
Beginning balance (in shares) at Sep. 30, 2022	37,591	37,591
Shares of common stock
Stock-based compensation (in shares)		838
Stock option exercises (in shares)		0
Sale of common stock (in shares)		15,455
Ending balance (in shares) at Mar. 31, 2023	53,884	53,884
Balance, beginning of period at Sep. 30, 2022		$ 787,347	(47,721)	1,301	(622,099)
Shares of common stock
Stock-based compensation		3,269
Stock option exercises		0
Tax withholding paid on behalf of employees for stock-based awards		(144)
Sale of common stock		15,628
Translation adjustment	$ 55			(55)
Net (loss) income	(23,921)
Balance, end of period at Mar. 31, 2023	$ 113,605	$ 806,100	(47,721)	1,246	(646,020)
Beginning balance (in shares) at Dec. 31, 2022		37,868
Shares of common stock
Stock-based compensation (in shares)		561
Stock option exercises (in shares)		0
Sale of common stock (in shares)		15,455
Ending balance (in shares) at Mar. 31, 2023	53,884	53,884
Balance, beginning of period at Dec. 31, 2022		$ 789,080	(47,721)	1,254	(633,792)
Shares of common stock
Stock-based compensation		1,535
Stock option exercises		0
Tax withholding paid on behalf of employees for stock-based awards		(143)
Sale of common stock		15,628
Translation adjustment	$ 8			(8)
Net (loss) income					(12,228)
Balance, end of period at Mar. 31, 2023	$ 113,605	$ 806,100	$ (47,721)	$ 1,246	$ (646,020)