Borrowings - Schedule of Senior Notes (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ (41.1)	$ (21.0)
Senior notes, net ($248.2 and $239.7 due to related parties)	535.1	595.8
Senior Notes
Debt Instrument [Line Items]
Senior notes	574.1	645.0
Discount	(2.2)	(3.9)
Unamortized discount and debt issuance costs	$ 36.8	45.3
7.875% Senior Notes, Due 2026 \| Secured Debt
Debt Instrument [Line Items]
Interest rate (as a percent)	7.875%
Senior notes	$ 289.1	360.0
7.875% Senior Notes, Due 2026 \| Secured Debt \| Before March 15, 2025
Debt Instrument [Line Items]
Redemption price	101.969%
7.875% Senior Notes, Due 2026 \| Senior Notes
Debt Instrument [Line Items]
Discount	$ (0.4)	(0.9)
Unamortized debt issuance costs	$ (1.8)	(3.0)
12% Paid in Cash or 13.25% Paid in Kind Senior Notes, Due 2027
Debt Instrument [Line Items]
Interest rate (as a percent)	12.00%
12% Paid in Cash or 13.25% Paid in Kind Senior Notes, Due 2027 \| Secured Debt
Debt Instrument [Line Items]
Senior notes	$ 285.0	285.0
12% Paid in Cash or 13.25% Paid in Kind Senior Notes, Due 2027 \| Payment in Kind (PIK) Note
Debt Instrument [Line Items]
Interest rate (as a percent)	13.25%
12% Paid in Cash or 13.25% Paid in Kind Senior Notes, Due 2027 \| Senior Notes
Debt Instrument [Line Items]
Discount	$ (31.8)	(39.1)
Unamortized debt issuance costs	$ (5.0)	$ (6.2)

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

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