Leases (Narrative) (Details) - USD ($)	3 Months Ended	12 Months Ended
	Sep. 30, 2023	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2021
Lessee, Lease, Description [Line Items]
Operating lease expense		$ 109,900,000	$ 105,300,000	$ 89,500,000
Use of cash for payments on operating leases		337,800,000	128,000,000.0	98,800,000
Noncash ROU asset additions		150,000,000	$ 252,000,000	$ 259,000,000
Sales-type Lease, Residual Value of Leased Asset	$ 0	0
Variable Interest Entity, Primary Beneficiary | Land | NEOM Green Hydrogen Company
Lessee, Lease, Description [Line Items]
Use of cash for payments on operating leases	$ 209,000,000	$ 209,000,000