Long-Term Debt - Schedule of Long-Term Debt (Details) - USD ($) $ in Millions	Sep. 30, 2022	Sep. 30, 2021
Debt Instrument [Line Items]
Financing costs, net	$ (10.6)	$ (11.1)
Total debt, net	1,342.7	1,141.0
Less: Current portion of long-term debt	12.0	10.4
Long-term debt, net	1,330.7	1,130.6
Series B Term Loan
Debt Instrument [Line Items]
Debt instruments net of original issue discount	1,185.3	1,001.7
Receivables Financing Agreement
Debt Instrument [Line Items]
Debt instruments net of original issue discount	$ 168.0	$ 150.4

Debt instrument carrying amount net of issue discount.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt, classified as current. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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Amount, excluding unamortized premium (discount) and debt issuance cost, of long-term debt classified as noncurrent. Excludes lease obligation.

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