Accrued Expenses and Other Current Liabilities - Schedule of Accrued Expenses and Other Current Liabilities (Details) - USD ($) $ in Millions		Sep. 30, 2023	Sep. 30, 2022
Payables and Accruals [Abstract]
Payroll related accruals		$ 52.2	$ 46.0
Accrued operating expenses		77.8	91.2
Other accruals (a)	[1]	50.2	56.3
Accrued expenses and other current liabilities		$ 180.2	$ 193.5

[1] Other accruals for the fiscal year ended September 30, 2022 includes the Company’s deferral of Federal Insurance Contributions Act (FICA) payroll tax under the CARES Act.