Financial Instruments (Gains and Losses Recognized In Other Comprehensive Income (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Net Investment Hedging Relationships
Tax effects	$ (4.0)	$ 81.0	$ (18.4)	$ 69.1
Net Amount Recognized in OCI	40.4	528.4	8.4	6.7
Derivatives in Cash Flow Hedging Relationships
Tax effects	(6.3)	(17.1)	(5.1)	1.0
Net Amount Recognized in OCI	42.5	40.9	77.1	61.6
Net investment hedges
Net Investment Hedging Relationships
Total Amount Recognized in OCI	15.2	(312.1)	63.9	(249.8)
Tax effects	(3.7)	75.3	(15.4)	59.9
Net Amount Recognized in OCI	11.5	(236.8)	48.5	(189.9)
Net investment hedges | Forward exchange contracts
Net Investment Hedging Relationships
Total Amount Recognized in OCI	(0.5)	(35.2)	(3.9)	(1.3)
Net investment hedges | Foreign currency debt
Net Investment Hedging Relationships
Total Amount Recognized in OCI	42.5	(276.9)	97.3	(248.9)
Net investment hedges | Cross currency interest rate swaps(A)
Net Investment Hedging Relationships
Total Amount Recognized in OCI	(26.8)	0.0	(29.5)	0.4
Cash flow hedges
Derivatives in Cash Flow Hedging Relationships
Total Amount Recognized in OCI	48.8	58.0	82.2	60.6
Tax effects	(6.3)	(17.1)	(5.1)	1.0
Net Amount Recognized in OCI	42.5	40.9	77.1	61.6
Cash flow hedges | Forward exchange contracts
Derivatives in Cash Flow Hedging Relationships
Total Amount Recognized in OCI	19.6	80.3	10.5	(54.1)
Cash flow hedges | Forward exchange contracts, excluded components
Derivatives in Cash Flow Hedging Relationships
Total Amount Recognized in OCI	(4.5)	(1.8)	(14.9)	(8.1)
Cash flow hedges | Other
Derivatives in Cash Flow Hedging Relationships
Total Amount Recognized in OCI	$ 33.7	$ (20.5)	$ 86.6	$ 122.8