Long-Term Debt - Scheduled Maturities of Long-Term Debt (Details) - USD ($) $ in Millions	Dec. 31, 2021	Sep. 30, 2021
Debt Disclosure [Abstract]
2022	$ 7.8
2023	10.4
2024	235.8
2025	972.2
Total long-term debt	1,226.2
Less: Current portion of long-term debt	10.4	$ 10.4
Less: Original issue discount	1.6
Less: Financing costs	10.2
Long-term debt, net	$ 1,204.0	$ 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, 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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