Financial Instruments and Risk Management (Schedule of Fair Value of Assets and Liabilities Measured on a Recurring Basis) (Details) - Level 2 - Recurring fair value measurement - USD ($) $ in Millions	Sep. 30, 2024	Sep. 30, 2023
Derivative [Line Items]
Deferred compensation	$ (21.1)	$ (19.4)
Net liabilities at estimated fair value	(23.4)	(13.8)
FX contract
Derivative [Line Items]
Estimated fair value of derivatives	$ (2.3)	$ 5.6