CONDENSED CONSOLIDATED STATEMENTS OF SHAREHOLDERS' EQUITY - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Treasury Stock	Accumulated other comprehensive income, beginning and end of period	Pension adjustment
Beginning balance (in shares) at Sep. 30, 2022		3,759
Shares of common stock
Stock-based compensation (in shares)		84
Sale of common stock (in shares)		1,545
Ending balance (in shares) at Mar. 31, 2023		5,388
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
Tax withholding paid on behalf of employees for stock-based awards		(144)
Sale of common stock		15,628
Pension adjustment				(55)
Net loss	$ (23,921)				(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		3,787
Shares of common stock
Stock-based compensation (in shares)		56
Sale of common stock (in shares)		1,545
Ending balance (in shares) at Mar. 31, 2023		5,388
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
Tax withholding paid on behalf of employees for stock-based awards		(143)
Sale of common stock		15,628
Pension adjustment				(8)
Net loss	(12,228)				(12,228)
Balance, end of period at Mar. 31, 2023	$ 113,605	$ 806,100	(47,721)	1,246	(646,020)
Beginning balance (in shares) at Sep. 30, 2023	7,711	7,711
Shares of common stock
Stock-based compensation (in shares)		493
Ending balance (in shares) at Mar. 31, 2024	8,204	8,204
Balance, beginning of period at Sep. 30, 2023		$ 825,119	(47,721)	350	(697,458)
Shares of common stock
Stock-based compensation		1,261
Stock issuance costs		(18)
Tax withholding paid on behalf of employees for stock-based awards		(24)
Net loss	$ (14,174)				(14,174)
Balance, end of period at Mar. 31, 2024	$ 67,335	$ 826,338	(47,721)	350	(711,632)
Beginning balance (in shares) at Dec. 31, 2023		7,730
Shares of common stock
Stock-based compensation (in shares)		474
Ending balance (in shares) at Mar. 31, 2024	8,204	8,204
Balance, beginning of period at Dec. 31, 2023		$ 825,948	(47,721)	350	(703,137)
Shares of common stock
Stock-based compensation		413
Tax withholding paid on behalf of employees for stock-based awards		(23)
Net loss	$ (8,495)				(8,495)
Balance, end of period at Mar. 31, 2024	$ 67,335	$ 826,338	$ (47,721)	$ 350	$ (711,632)