CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (LOSS) (Unaudited) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Statement of Comprehensive Income [Abstract]
Net income (loss)	$ 13,053	$ (111,831)	$ 220,400	$ 119,023
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 $(270), respectively	262	264	789	758
Adjustment to postemployment benefit obligation, net of tax of $(232), $(245), $(697) and $(734), respectively	768	812	2,302	2,437
Other comprehensive income	1,030	1,076	3,091	3,195
Comprehensive income (loss)	$ 14,083	$ (110,755)	$ 223,491	$ 122,218