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Borrowings - Schedule of Senior Notes (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2025	Dec. 31, 2024	Nov. 06, 2024
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ (29.9)	$ (35.4)
Senior notes, net	$ 488.0	487.4
2026
Debt Instrument [Line Items]
Redemption price	104.938%
Before March 15, 2025
Debt Instrument [Line Items]
Redemption price	102.469%
2028 and thereafter
Debt Instrument [Line Items]
Redemption price	100.00%
Senior Notes
Debt Instrument [Line Items]
Outstanding borrowings (MSR financing facilities, net)	$ 488.0	487.4
Senior Notes Due 2029
Debt Instrument [Line Items]
Interest rate (as a percent)			9.875%
Senior Notes Due 2029 \| 2026
Debt Instrument [Line Items]
Redemption price	100.00%
Senior Notes Due 2029 \| Before March 15, 2025
Debt Instrument [Line Items]
Redemption price	40.00%
Senior Notes Due 2029 \| Senior Notes
Debt Instrument [Line Items]
Interest rate (as a percent)	9.875%
Unamortized discount and debt issuance costs	$ (12.0)	(12.6)
Total Financing liabilities	$ 500.0	$ 500.0