Financial Instruments (Fair Value and Balance Sheet Location of Derivatives) (Details) - USD ($) $ in Millions	Jun. 30, 2026	Sep. 30, 2025
Derivative [Line Items]
Total Derivatives, Assets	$ 365.0	$ 244.4
Total Derivatives, Liabilities	207.3	93.6
Designated as hedging instrument
Derivative [Line Items]
Total Derivatives, Assets	358.6	212.1
Total Derivatives, Liabilities	174.4	48.9
Designated as hedging instrument | Balance Sheet Location [Axis]: us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Liabilities	58.6	21.4
Designated as hedging instrument | Balance Sheet Location [Axis]: us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Liabilities	32.6	0.3
Designated as hedging instrument | Balance Sheet Location [Axis]: us-gaap:OtherAssetsCurrent | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Assets	59.3	50.7
Designated as hedging instrument | Balance Sheet Location [Axis]: us-gaap:OtherAssetsCurrent | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Assets	19.5	13.1
Designated as hedging instrument | Balance Sheet Location [Axis]: us-gaap:OtherAssetsNoncurrent | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Assets	20.7	10.1
Designated as hedging instrument | Balance Sheet Location [Axis]: us-gaap:OtherAssetsNoncurrent | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Assets	259.1	138.2
Designated as hedging instrument | Balance Sheet Location [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Liabilities	3.2	3.4
Designated as hedging instrument | Balance Sheet Location [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Liabilities	80.0	23.8
Not designated as hedging instrument
Derivative [Line Items]
Total Derivatives, Assets	6.4	32.3
Total Derivatives, Liabilities	32.9	44.7
Not designated as hedging instrument | Balance Sheet Location [Axis]: us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Liabilities	2.8	14.2
Not designated as hedging instrument | Balance Sheet Location [Axis]: us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Liabilities	1.3	0.0
Not designated as hedging instrument | Balance Sheet Location [Axis]: us-gaap:OtherAssetsCurrent | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Assets	6.2	17.8
Not designated as hedging instrument | Balance Sheet Location [Axis]: us-gaap:OtherAssetsCurrent | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Assets	0.0	0.0
Not designated as hedging instrument | Balance Sheet Location [Axis]: us-gaap:OtherAssetsNoncurrent | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Assets	0.2	2.7
Not designated as hedging instrument | Balance Sheet Location [Axis]: us-gaap:OtherAssetsNoncurrent | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Assets	0.0	11.8
Not designated as hedging instrument | Balance Sheet Location [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Forward exchange contracts
Derivative [Line Items]
Total Derivatives, Liabilities	28.8	30.5
Not designated as hedging instrument | Balance Sheet Location [Axis]: us-gaap:OtherLiabilitiesNoncurrent | Interest Rate Management Contracts
Derivative [Line Items]
Total Derivatives, Liabilities	$ 0.0	$ 0.0