Assets and Liabilities, at Fair Value - Narrative (Details) - USD ($) $ in Millions	Dec. 31, 2023	Sep. 30, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying value	$ 342.9	$ 342.1
Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, fair value	$ 351.9
Senior Secured Notes due 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt instrument, interest rate, stated percentage	8.625%

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

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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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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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