Borrowings - Schedule of Senior Notes (Details) - USD ($) $ in Millions	6 Months Ended
Jun. 30, 2024	Dec. 31, 2023
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ (33.9)	$ (21.0)
Senior notes, net ($245.3 and $239.7 due to related parties)	555.2	595.8
Senior Notes
Debt Instrument [Line Items]
Senior notes	597.6	645.0
Discount	(2.7)	(3.9)
Unamortized discount and debt issuance costs	$ 39.7	45.3
7.875% Senior Notes, Due 2026 \| Secured Debt
Debt Instrument [Line Items]
Interest rate (as a percent)	7.875%
Senior notes	$ 312.6	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	$ (0.6)	(0.9)
Unamortized debt issuance costs	$ (2.1)	(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	$ (34.3)	(39.1)
Unamortized debt issuance costs	$ (5.4)	$ (6.2)

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

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