Residential Loans and Residential Loans Held for Sale, at Fair Value - Schedule of Components of Net Gain (Loss) on Residential Mortgage Loans at Fair Value (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2026	Sep. 30, 2025	Sep. 30, 2026	Sep. 30, 2025
VIE, Primary Beneficiary \| Consolidated SLST
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Unrealized (losses) gains, net	$ (29,568)	$ 7,395	$ (47,178)	$ 37,100
Residential loans
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Unrealized (losses) gains, net	(8,823)	6,575	(16,134)	14,552
Residential loans held in securitization trusts
SEC Schedule, 12-29, Real Estate Companies, Investment in Mortgage Loans on Real Estate [Line Items]
Unrealized (losses) gains, net	$ (105,898)	$ 12,958	$ (122,909)	$ 45,711

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details