Basis of Presentation and Accounting Policies - Narrative (Details) - USD ($) shares in Millions, $ in Millions	3 Months Ended		9 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021	Sep. 30, 2021
Accounting Policies [Abstract]
Allowance for doubtful accounts	$ 15.9		$ 15.9		$ 13.2
Allowance for certain customer returns, rebates and incentives	$ 11.9		$ 11.9		$ 6.7
Antidilutive share-based compensation awards (in shares)	0.6	0.2	0.4	0.2
Capital expenditures in accounts payable or other current liabilities at period end			$ 15.5	$ 18.0
Outstanding purchase of common stock recorded in accounts payable			$ 8.8	$ 1.8