Basis of Presentation and Accounting Policies - Narrative (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Sep. 30, 2024
Accounting Policies [Abstract]
Allowance for doubtful accounts	$ 24.0		$ 22.0
Antidilutive share-based compensation awards (in shares)	0.7	0.5
Capital expenditures in accounts payable or other current liabilities at period end	$ 11.0	$ 21.0
Outstanding purchase of common stock recorded in accounts payable	1.0	$ 1.0
Supplier finance program, obligation	$ 68.0		$ 77.0