Securitizations and Variable Interest Entities - Schedule Of Securitization Reverse Mortgage Loans Buyouts And Financing Liabilities (Details) - USD ($) $ in Millions	Sep. 30, 2026	Dec. 31, 2025	Sep. 30, 2025
Qualitative and Quantitative Information, Transferor's Continuing Involvement [Line Items]
Receivables, net	$ 270.0	$ 189.8
Debt service accounts	47.8		$ 35.1
Mortgage warehouse facilities	1,430.1	1,224.6
Liabilities	10,662.4	15,492.8
Other restricted cash	52.1		$ 63.4
Total Assets	11,320.9	16,170.6
Variable Interest Entity, Primary Beneficiary
Qualitative and Quantitative Information, Transferor's Continuing Involvement [Line Items]
Receivables, net	84.3	64.2
Variable Interest Entity, Primary Beneficiary \| OLIT Securitization Notes
Qualitative and Quantitative Information, Transferor's Continuing Involvement [Line Items]
Mortgages Held-for-sale, Fair Value Disclosure	1,316.1	698.2
Receivables, net	84.3	62.6
Real estate owned	145.2	81.0
Mortgage warehouse facilities	1,802.0	951.9
Unamortized discount and debt issuance costs	(102.6)	(52.6)
Accrued expenses (Other liabilities)	3.1	2.6
Liabilities	1,702.5	901.9
Other restricted cash	38.0	26.5
Total Assets	$ 1,583.6	$ 868.4

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