Long-Term Debt - Scheduled Maturities of Long-Term Debt (Details) - USD ($) $ in Millions	Jun. 30, 2022	Sep. 30, 2021
Debt Disclosure [Abstract]
2022	$ 3.0
2023	12.0
2024	12.0
2025	183.4
2026 and thereafter	1,161.0
Total long-term debt	1,371.4
Less: Current maturities of long-term debt	12.0	$ 10.4
Less: Original issue discount	12.1
Less: Financing costs	10.9
Total long-term debt, net	$ 1,336.4	$ 1,130.6

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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Amount of debt discount to be amortized after one year or the normal operating cycle, if longer.

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

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