CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE (LOSS) INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2025	Jun. 30, 2024	Jun. 30, 2025	Jun. 30, 2024
Statement of Comprehensive Income [Abstract]
Net (loss) income	$ (15,051)	$ (11,574)	$ 320,555	$ 198,649
Other comprehensive income (loss), net of tax
Reclassifications of losses to net (loss) income on derivatives designated as hedging instruments, net of tax of $(79), $(79), $(238) and $(238), respectively	264	264	790	790
Adjustment to postemployment benefit obligation, net of tax of $58, $112, $174 and $(2,836), respectively	(196)	(369)	(587)	9,386
Other comprehensive income (loss), net of tax	68	(105)	203	10,176
Comprehensive (loss) income	$ (14,983)	$ (11,679)	$ 320,758	$ 208,825