Financial Instruments (Fair Value and Balance Sheet Location of Derivatives) (Details) - USD ($) $ in Millions	Dec. 31, 2023	Sep. 30, 2023
Derivative [Line Items]
Total Derivatives, Assets	$ 153.2	$ 394.1
Total Derivatives, Liabilities	122.3	211.4
Designated as hedging instrument
Derivative [Line Items]
Total Derivatives, Assets	148.2	383.8
Total Derivatives, Liabilities	116.7	206.8
Designated as hedging instrument | Other Receivables and Current Assets | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Assets	61.1	50.2
Designated as hedging instrument | Other Receivables and Current Assets | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Assets	7.9	13.0
Designated as hedging instrument | Other Noncurrent Assets | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Assets	13.9	19.8
Designated as hedging instrument | Other Noncurrent Assets | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Assets	65.3	300.8
Designated as hedging instrument | Payables and Accrued Liabilities | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Liabilities	37.2	94.1
Designated as hedging instrument | Payables and Accrued Liabilities | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Liabilities	0.2	0.0
Designated as hedging instrument | Other Noncurrent Liabilities | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Liabilities	19.2	25.7
Designated as hedging instrument | Other Noncurrent Liabilities | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Liabilities	60.1	87.0
Not designated as hedging instrument
Derivative [Line Items]
Total Derivatives, Assets	5.0	10.3
Total Derivatives, Liabilities	5.6	4.6
Not designated as hedging instrument | Other Receivables and Current Assets | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Assets	3.7	6.4
Not designated as hedging instrument | Other Receivables and Current Assets | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Assets	1.2	3.9
Not designated as hedging instrument | Other Noncurrent Assets | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Assets	0.1	0.0
Not designated as hedging instrument | Payables and Accrued Liabilities | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Liabilities	5.5	4.6
Not designated as hedging instrument | Payables and Accrued Liabilities | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Liabilities	0.0	0.0
Not designated as hedging instrument | Other Noncurrent Liabilities | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Liabilities	$ 0.1	$ 0.0