CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022
Statement of Comprehensive Income [Abstract]
Net income	$ 1,532	$ 13,053	$ 227,700	$ 220,400
Other comprehensive income, net of tax
Reclassifications of losses to net income on derivatives designated as hedging instruments, net of tax of $(79), $(79), $(238) and $(238), respectively	263	262	790	789
Adjustment to postemployment benefit obligation, net of tax of $(12), $(232), $(37) and $(697), respectively	41	768	123	2,302
Other comprehensive income, net of tax	304	1,030	913	3,091
Comprehensive income	$ 1,836	$ 14,083	$ 228,613	$ 223,491