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

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Assets and Liabilities, at Fair Value - Narrative (Details) - USD ($) $ in Millions	Mar. 31, 2024	Mar. 01, 2024	Sep. 30, 2023
Senior Secured Notes due 2025
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying value	$ 343.7		$ 342.1
Senior Secured Notes due 2025 \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt instrument, interest rate, stated percentage	8.625%	8.625%
Senior Secured Notes due 2025 \| Level 2 \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, fair value	$ 349.4
Senior Secured Notes due 2031
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Carrying value	542.2		$ 0.0
Senior Secured Notes due 2031 \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Debt instrument, interest rate, stated percentage		7.875%
Senior Secured Notes due 2031 \| Level 2 \| Senior Notes
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Long-term debt, fair value	$ 557.8