Financial Instruments (Fair Value and Balance Sheet Location of Derivatives) (Details) - USD ($) $ in Millions	Mar. 31, 2023	Sep. 30, 2022
Derivative [Line Items]
Total Derivatives, Assets	$ 125.8	$ 189.1
Total Derivatives, Liabilities	169.8	366.5
Designated as hedging instrument
Derivative [Line Items]
Total Derivatives, Assets	121.0	181.6
Total Derivatives, Liabilities	165.1	364.3
Designated as hedging instrument | Other Receivables and Current Assets | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Assets	82.1	71.6
Designated as hedging instrument | Other Receivables and Current Assets | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Assets	8.5	36.7
Designated as hedging instrument | Other Noncurrent Assets | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Assets	23.5	60.8
Designated as hedging instrument | Other Noncurrent Assets | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Assets	6.9	12.5
Designated as hedging instrument | Payables and Accrued Liabilities | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Liabilities	67.2	226.2
Designated as hedging instrument | Payables and Accrued Liabilities | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Liabilities	2.5	0.0
Designated as hedging instrument | Other Noncurrent Liabilities | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Liabilities	12.9	46.9
Designated as hedging instrument | Other Noncurrent Liabilities | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Liabilities	82.5	91.2
Not designated as hedging instrument
Derivative [Line Items]
Total Derivatives, Assets	4.8	7.5
Total Derivatives, Liabilities	4.7	2.2
Not designated as hedging instrument | Other Receivables and Current Assets | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Assets	4.4	6.1
Not designated as hedging instrument | Other Receivables and Current Assets | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Assets	0.2	0.0
Not designated as hedging instrument | Other Noncurrent Assets | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Assets	0.2	0.1
Not designated as hedging instrument | Other Noncurrent Assets | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Assets	0.0	1.3
Not designated as hedging instrument | Payables and Accrued Liabilities | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Liabilities	4.6	2.1
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	0.1
Not designated as hedging instrument | Other Noncurrent Liabilities | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Liabilities	$ 0.0	$ 0.0