CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2025	Mar. 31, 2024	Mar. 31, 2025	Mar. 31, 2024
Statement of Comprehensive Income [Abstract]
Net income	$ 204,287	$ 120,812	$ 335,606	$ 210,223
Other comprehensive income, net of tax
Reclassifications of losses to net income on derivatives designated as hedging instruments, net of tax of $(80), $(80), $(159) and $(159), respectively	263	262	526	526
Adjustment to postemployment benefit obligation, net of tax of $58, $(2,908), $116 and $(2,948), respectively	(196)	9,624	(391)	9,755
Other comprehensive income, net of tax	67	9,886	135	10,281
Comprehensive income	$ 204,354	$ 130,698	$ 335,741	$ 220,504