Reverse Mortgages - By Type (Details) - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Reverse loans held for sale pooled into Home Equity Conversion Mortgage Backed Securities (HMBS), at fair value	$ 9,807.5	$ 0.0
Total fair value		11,125.3	$ 7,970.0	$ 7,504.1
HECM Loans - Securitized, Pledged To HMBS-Related Borrowings
Accounts, Notes, Loans and Financing Receivable [Line Items]
Reverse loans held for sale pooled into Home Equity Conversion Mortgage Backed Securities (HMBS), at fair value	9,703.1
Total fair value		10,950.8
New HECM Loan Originations And HECM Loan Tails - Unsecuritized
Accounts, Notes, Loans and Financing Receivable [Line Items]
Reverse loans held for sale pooled into Home Equity Conversion Mortgage Backed Securities (HMBS), at fair value	104.4
Total fair value		174.5
New HECM loan originations pending pooling into HMBS (pipeline loans)	$ 58.4	$ 87.4