Business and Asset Actions (Global Cost Reduction Plan) (Details) $ in Millions	12 Months Ended	28 Months Ended
Sep. 30, 2025 USD ($)	Sep. 30, 2024 USD ($)	Sep. 30, 2023 USD ($)	Sep. 30, 2025 USD ($) employee
Restructuring Cost and Reserve [Line Items]
Charge for severance and other postemployment benefits	$ 123.7	$ 57.0	$ 27.0
Global Cost Reduction Plan
Restructuring Cost and Reserve [Line Items]
Charge for severance and other postemployment benefits	123.7	57.0	27.0	$ 207.7
Number of positions eliminated \| employee				3,600
Cash payments	(57.5)	(43.6)	(6.8)
Currency translation adjustment	(1.4)	(0.8)	0.4
Amount accrued	$ 101.6	$ 34.0	$ 19.8	$ 101.6

Amount of cash payments made as the result of exit or disposal activities. Excludes payments associated with a discontinued operation or an asset retirement obligation.

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