Residential Whole Loans - Vintage Information Regarding Residential Whole Loans (Details) - Residential whole loans - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Non-QM loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 5,122,926	$ 4,291,086
Business purpose loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	2,642,818	3,396,181
Business purpose loans \| Single-family rental loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,246,595	1,356,400
Business purpose loans \| Single-family transitional loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	792,079	1,100,855
Business purpose loans \| Multifamily transitional loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	604,144	938,926
Legacy RPL/NPL loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,006,236	1,082,549
Other loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	51,937	52,073
Estimated Fair Value
Accounts, Notes, Loans and Financing Receivable [Line Items]
2025	1,571,213
2024	1,426,147
2023	1,200,203
2022	1,259,961
2021	1,608,791
Prior	618,550
Total	7,684,865
Estimated Fair Value \| Non-QM loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
2025	1,233,263
2024	1,006,871
2023	565,190
2022	540,026
2021	1,132,462
Prior	29,653
Total	4,507,465	3,568,694
Estimated Fair Value \| Business purpose loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	2,543,744	3,265,548
Estimated Fair Value \| Business purpose loans \| Single-family rental loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
2025	43,816
2024	41,040
2023	219,207
2022	501,361
2021	342,007
Prior	7,141
Total	1,154,572	1,248,197
Estimated Fair Value \| Business purpose loans \| Single-family transitional loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
2025	294,134
2024	308,854
2023	148,401
2022	29,446
2021	4,156
Prior	37
Total	785,028	1,078,425
Estimated Fair Value \| Business purpose loans \| Multifamily transitional loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
2025	0
2024	69,382
2023	267,405
2022	189,128
2021	78,229
Prior	0
Total	604,144	938,926
Estimated Fair Value \| Legacy RPL/NPL loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
2025	0
2024	0
2023	0
2022	0
2021	0
Prior	581,719
Total	581,719	624,895
Estimated Fair Value \| Other loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
2025	0
2024	0
2023	0
2022	0
2021	51,937
Prior	0
Total	$ 51,937	$ 52,073

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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