Credit Facilities Senior Secured Notes due 2025 (Details) - USD ($) $ in Millions	9 Months Ended
Jun. 30, 2020	Sep. 30, 2019
Debt Instrument [Line Items]
Senior Notes	$ 336.9	$ 0.0
Debt Instrument, Face Amount	$ 350.0
Debt Instrument, Interest Rate, Stated Percentage	8.625%
Debt Issuance Costs, Gross	$ 8.0
Debt Instrument, Redemption Price, Percentage of Principal Amount Redeemed	40.00%
Debt Instrument, Redemption Price, Percentage	108.625%
Senior Notes [Member]
Debt Instrument [Line Items]
Debt Instrument, Unamortized Discount (Premium) and Debt Issuance Costs, Net	$ 13.1

Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Percentage of principal amount of debt redeemed.

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Amount of unamortized debt discount (premium) and debt issuance costs.

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

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Including the current and noncurrent portions, carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer). Senior note holders are paid off in full before any payments are made to junior note holders.

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