Long-Term Debt - Schedule of Long-Term Debt (Details) - USD ($) $ in Millions	Mar. 31, 2026	Sep. 30, 2025
Debt Instrument [Line Items]
Financing costs, net	$ (4.3)	$ (5.3)
Total debt, net	823.9	790.2
Less: Current portion of long-term debt	0.0	0.0
Long-term debt, net	823.9	790.2
Series B Term Loan
Debt Instrument [Line Items]
Debt instruments net of original issue discount	734.5	733.9
Receivables Financing Agreement
Debt Instrument [Line Items]
Debt instruments net of original issue discount	$ 93.7	$ 61.6

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details

- Definition

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

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