CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ (11,044)	$ (23,906)	$ 70,309	$ 51,674
Other comprehensive income (loss):
Unrealized gain on pension plan obligation	317	382	955	1,144
Tax effect of unrealized gain on pension plan obligation	(80)	(104)	(240)	(305)
Unrealized gain (loss) on captive insurance collateral	401	(50)	1,596	1,080
Tax effect of unrealized gain (loss) on captive insurance collateral	(84)	11	(336)	(227)
Unrealized gain (loss) on interest rate hedges	(186)	571	(1,007)	(510)
Tax effect of unrealized gain (loss) on interest rate hedges	50	(151)	270	137
Total other comprehensive income	418	659	1,238	1,319
Total comprehensive income (loss)	$ (10,626)	$ (23,247)	$ 71,547	$ 52,993