Financial Instruments and Risk Management - Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis (Details) - USD ($) $ in Millions	Jun. 30, 2026	Sep. 30, 2025
Level 2 \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Deferred compensation	$ (20.1)	$ (20.6)
Net Assets at estimated fair value	1.9	1.8
Foreign currency contracts \| Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - Foreign Currency contracts	(1.6)	(0.5)
Foreign currency contracts \| Level 2 \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - Foreign Currency contracts	0.8	(3.9)
Foreign currency contracts \| Level 2 \| Fair Value, Measurements, Recurring \| Not Designated as Hedging Instrument
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - Foreign Currency contracts	(1.6)	(0.5)
Derivatives - Interest Rate Swap \| Level 2 \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - Foreign Currency contracts	19.4	25.3
Commodity contract \| Level 2 \| Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivatives - Foreign Currency contracts	3.4	1.5
Estimate of Fair Value Measurement
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term Debt, Percentage Bearing Fixed Interest, Fair Value Amount	$ 2,456.6	$ 2,473.5