Financial Instruments (Fair Value and Balance Sheet Location of Derivatives) (Details) - USD ($) $ in Millions	Sep. 30, 2024	Sep. 30, 2023
Derivative [Line Items]
Total Derivatives, Assets	$ 142.6	$ 394.1
Total Derivatives, Liabilities	100.6	211.4
Designated as Hedging Instrument
Derivative [Line Items]
Total Derivatives, Assets	119.6	383.8
Total Derivatives, Liabilities	78.6	206.8
Not Designated as Hedging Instrument
Derivative [Line Items]
Total Derivatives, Assets	23.0	10.3
Total Derivatives, Liabilities	22.0	4.6
Forward exchange contracts | Designated as Hedging Instrument | Other receivables and current assets
Derivative [Line Items]
Total Derivatives, Assets	74.5	50.2
Forward exchange contracts | Designated as Hedging Instrument | Other noncurrent assets
Derivative [Line Items]
Total Derivatives, Assets	9.6	19.8
Forward exchange contracts | Designated as Hedging Instrument | Payables and accrued liabilities
Derivative [Line Items]
Total Derivatives, Liabilities	21.6	94.1
Forward exchange contracts | Designated as Hedging Instrument | Other noncurrent liabilities
Derivative [Line Items]
Total Derivatives, Liabilities	15.6	25.7
Forward exchange contracts | Not Designated as Hedging Instrument | Other receivables and current assets
Derivative [Line Items]
Total Derivatives, Assets	16.5	6.4
Forward exchange contracts | Not Designated as Hedging Instrument | Other noncurrent assets
Derivative [Line Items]
Total Derivatives, Assets	0.2	0.0
Forward exchange contracts | Not Designated as Hedging Instrument | Payables and accrued liabilities
Derivative [Line Items]
Total Derivatives, Liabilities	21.8	4.6
Forward exchange contracts | Not Designated as Hedging Instrument | Other noncurrent liabilities
Derivative [Line Items]
Total Derivatives, Liabilities	0.2	0.0
Interest rate management contracts | Designated as Hedging Instrument | Other receivables and current assets
Derivative [Line Items]
Total Derivatives, Assets	1.2	13.0
Interest rate management contracts | Designated as Hedging Instrument | Other noncurrent assets
Derivative [Line Items]
Total Derivatives, Assets	34.3	300.8
Interest rate management contracts | Designated as Hedging Instrument | Payables and accrued liabilities
Derivative [Line Items]
Total Derivatives, Liabilities	1.2	0.0
Interest rate management contracts | Designated as Hedging Instrument | Other noncurrent liabilities
Derivative [Line Items]
Total Derivatives, Liabilities	40.2	87.0
Interest rate management contracts | Not Designated as Hedging Instrument | Other receivables and current assets
Derivative [Line Items]
Total Derivatives, Assets	1.7	3.9
Interest rate management contracts | Not Designated as Hedging Instrument | Other noncurrent assets
Derivative [Line Items]
Total Derivatives, Assets	4.6	0.0
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