EMPLOYEE BENEFIT PLANS - COMPONENTS OF NET PERIODIC COST (Details) - USD ($) $ in Thousands	12 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2020
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Defined Benefit Plan, Net Periodic Benefit Cost (Credit) Excluding Service Cost, Statement of Income or Comprehensive Income [Extensible Enumeration]	Other income, net
Pension
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	$ 8,291	$ 8,730	$ 8,223
Interest cost	9,632	9,112	10,587
Expected return on plan assets	(21,275)	(20,150)	(20,579)
Recognized actuarial loss	8,745	11,446	10,424
Prior service cost (credit) amortization	101	102	102
Net periodic benefit cost recognized as expense	5,494	9,240	8,757
OPEB
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Service cost	4,305	4,844	4,854
Interest cost	6,355	6,071	7,026
Expected return on plan assets	(7,575)	(6,497)	(6,510)
Recognized actuarial loss	5,684	7,909	7,442
Prior service cost (credit) amortization	(144)	(179)	(197)
Net periodic benefit cost recognized as expense	$ 8,625	$ 12,148	$ 12,615