Residential Loans and Residential Loans Held for Sale, at Fair Value - Schedule of Geographic Concentration of Credit Risk (Details) - Geographic Concentration Risk	3 Months Ended	12 Months Ended
Mar. 31, 2026	Dec. 31, 2025
Residential loans \| Florida
Concentration Risk [Line Items]
Geographic concentration, percent	9.10%	7.00%
Residential loans \| New Jersey
Concentration Risk [Line Items]
Geographic concentration, percent	8.90%	8.90%
Residential loans \| California
Concentration Risk [Line Items]
Geographic concentration, percent	7.60%	3.40%
Residential loans \| Ohio
Concentration Risk [Line Items]
Geographic concentration, percent	7.40%	10.70%
Residential loans \| Pennsylvania
Concentration Risk [Line Items]
Geographic concentration, percent	7.20%	10.10%
Residential loans \| New York
Concentration Risk [Line Items]
Geographic concentration, percent	6.10%	6.70%
Residential loans \| Texas
Concentration Risk [Line Items]
Geographic concentration, percent	5.50%	5.20%
Residential loans \| Illinois
Concentration Risk [Line Items]
Geographic concentration, percent	3.80%	3.60%
Consolidated SLST \| VIE, Primary Beneficiary \| Florida
Concentration Risk [Line Items]
Geographic concentration, percent	8.60%	8.60%
Consolidated SLST \| VIE, Primary Beneficiary \| New Jersey
Concentration Risk [Line Items]
Geographic concentration, percent	6.20%	6.30%
Consolidated SLST \| VIE, Primary Beneficiary \| California
Concentration Risk [Line Items]
Geographic concentration, percent	11.30%	11.20%
Consolidated SLST \| VIE, Primary Beneficiary \| Ohio
Concentration Risk [Line Items]
Geographic concentration, percent	3.40%	3.50%
Consolidated SLST \| VIE, Primary Beneficiary \| Pennsylvania
Concentration Risk [Line Items]
Geographic concentration, percent	3.80%	3.80%
Consolidated SLST \| VIE, Primary Beneficiary \| New York
Concentration Risk [Line Items]
Geographic concentration, percent	10.80%	10.70%
Consolidated SLST \| VIE, Primary Beneficiary \| Texas
Concentration Risk [Line Items]
Geographic concentration, percent	4.40%	4.40%
Consolidated SLST \| VIE, Primary Beneficiary \| Illinois
Concentration Risk [Line Items]
Geographic concentration, percent	7.40%	7.40%
Residential loans held in securitization trusts \| Florida
Concentration Risk [Line Items]
Geographic concentration, percent	8.50%	10.10%
Residential loans held in securitization trusts \| New Jersey
Concentration Risk [Line Items]
Geographic concentration, percent	6.90%	6.40%
Residential loans held in securitization trusts \| California
Concentration Risk [Line Items]
Geographic concentration, percent	13.20%	16.80%
Residential loans held in securitization trusts \| Ohio
Concentration Risk [Line Items]
Geographic concentration, percent	5.40%	3.90%
Residential loans held in securitization trusts \| Pennsylvania
Concentration Risk [Line Items]
Geographic concentration, percent	6.70%	5.50%
Residential loans held in securitization trusts \| New York
Concentration Risk [Line Items]
Geographic concentration, percent	7.10%	6.60%
Residential loans held in securitization trusts \| Texas
Concentration Risk [Line Items]
Geographic concentration, percent	6.20%	6.70%
Residential loans held in securitization trusts \| Illinois
Concentration Risk [Line Items]
Geographic concentration, percent	3.50%	3.30%
Residential loans held for sale \| New Jersey
Concentration Risk [Line Items]
Geographic concentration, percent	11.40%	9.20%
Residential loans held for sale \| Ohio
Concentration Risk [Line Items]
Geographic concentration, percent	13.40%	13.80%
Residential loans held for sale \| Pennsylvania
Concentration Risk [Line Items]
Geographic concentration, percent	11.40%	7.20%
Residential loans held for sale \| New York
Concentration Risk [Line Items]
Geographic concentration, percent	12.80%	11.90%
Residential loans held for sale \| Texas
Concentration Risk [Line Items]
Geographic concentration, percent	7.80%	8.90%

Residential loans | Florida