Long-Term Debt - Schedule of Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2022	Sep. 30, 2022
Debt Instrument [Line Items]
Financing costs, net	$ (10.2)	$ (10.6)
Total debt, net	1,421.5	1,342.7
Less: Current portion of long-term debt	12.0	12.0
Long-term debt, net	1,409.5	1,330.7
Series B Term Loan
Debt Instrument [Line Items]
Debt instruments net of original issue discount	1,182.7	1,185.3
Revolving Credit Agreement
Debt Instrument [Line Items]
Debt instruments net of original issue discount	24.0	0.0
Receivables Financing Agreement
Debt Instrument [Line Items]
Debt instruments net of original issue discount	$ 225.0	$ 168.0

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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