Financial Instruments (Fair Value and Balance Sheet Location of Derivatives) (Details) - USD ($) $ in Millions	Sep. 30, 2023	Sep. 30, 2022
Derivative [Line Items]
Total Derivatives, Assets	$ 394.1	$ 189.1
Total Derivatives, Liabilities	211.4	366.5
Designated as Hedging Instrument
Derivative [Line Items]
Total Derivatives, Assets	383.8	181.6
Total Derivatives, Liabilities	206.8	364.3
Not Designated as Hedging Instrument
Derivative [Line Items]
Total Derivatives, Assets	10.3	7.5
Total Derivatives, Liabilities	4.6	2.2
Forward exchange contracts | Designated as Hedging Instrument | Other receivables and current assets
Derivative [Line Items]
Total Derivatives, Assets	50.2	71.6
Forward exchange contracts | Designated as Hedging Instrument | Other noncurrent assets
Derivative [Line Items]
Total Derivatives, Assets	19.8	60.8
Forward exchange contracts | Designated as Hedging Instrument | Payables and accrued liabilities
Derivative [Line Items]
Total Derivatives, Liabilities	94.1	226.2
Forward exchange contracts | Designated as Hedging Instrument | Other noncurrent liabilities
Derivative [Line Items]
Total Derivatives, Liabilities	25.7	46.9
Forward exchange contracts | Not Designated as Hedging Instrument | Other receivables and current assets
Derivative [Line Items]
Total Derivatives, Assets	6.4	6.1
Forward exchange contracts | Not Designated as Hedging Instrument | Other noncurrent assets
Derivative [Line Items]
Total Derivatives, Assets	0.0	0.1
Forward exchange contracts | Not Designated as Hedging Instrument | Payables and accrued liabilities
Derivative [Line Items]
Total Derivatives, Liabilities	4.6	2.1
Forward exchange contracts | Not Designated as Hedging Instrument | Other noncurrent liabilities
Derivative [Line Items]
Total Derivatives, Liabilities	0.0	0.1
Interest rate management contracts | Designated as Hedging Instrument | Other receivables and current assets
Derivative [Line Items]
Total Derivatives, Assets	13.0	36.7
Interest rate management contracts | Designated as Hedging Instrument | Other noncurrent assets
Derivative [Line Items]
Total Derivatives, Assets	300.8	12.5
Interest rate management contracts | Designated as Hedging Instrument | Payables and accrued liabilities
Derivative [Line Items]
Total Derivatives, Liabilities	0.0	0.0
Interest rate management contracts | Designated as Hedging Instrument | Other noncurrent liabilities
Derivative [Line Items]
Total Derivatives, Liabilities	87.0	91.2
Interest rate management contracts | Not Designated as Hedging Instrument | Other receivables and current assets
Derivative [Line Items]
Total Derivatives, Assets	3.9	0.0
Interest rate management contracts | Not Designated as Hedging Instrument | Other noncurrent assets
Derivative [Line Items]
Total Derivatives, Assets	0.0	1.3
Interest rate management contracts | Not Designated as Hedging Instrument | Payables and accrued liabilities
Derivative [Line Items]
Total Derivatives, Liabilities	0.0	0.0
Interest rate management contracts | Not Designated as Hedging Instrument | Other noncurrent liabilities
Derivative [Line Items]
Total Derivatives, Liabilities	$ 0.0	$ 0.0