CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Mar. 31, 2024	Mar. 31, 2023
Statement of Comprehensive Income [Abstract]
Net income	$ 120,812	$ 110,247	$ 210,223	$ 226,168
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	262	264	526	527
Adjustment to postemployment benefit obligation, net of tax of $(2,908), $(13), $(2,948) and $(25), respectively	9,624	41	9,755	82
Other comprehensive income, net of tax	9,886	305	10,281	609
Comprehensive income	$ 130,698	$ 110,552	$ 220,504	$ 226,777