Long-Term Debt - Scheduled Maturities of Long-Term Debt (Details) - USD ($) $ in Millions	Jun. 30, 2020	Sep. 30, 2019
Debt Disclosure [Abstract]
2021	$ 10.4
2022	180.4
2023	10.4
2024	10.4
2025 and thereafter	974.6
Total long-term debt	1,186.2
Less: Current maturities	10.4	$ 10.4
Less: Original issue discount	2.0
Less: Financing costs	14.7
Long-term debt, net	$ 1,159.1	$ 1,134.2

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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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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 of long-term debt payable, sinking fund requirements, and other securities issued that are redeemable by holder at fixed or determinable prices and dates maturing after the fifth rolling twelve months following the latest balance sheet. For interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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