Residential Whole Loans - Vintage Information Regarding Residential Whole Loans (Details) - Residential whole loans - USD ($) $ in Thousands	Mar. 31, 2025	Dec. 31, 2024
Business purpose loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 3,139,060	$ 3,396,181
Business purpose loans \| Multifamily transitional loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	835,049	938,926
Business purpose loans \| Single-family rental loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,312,993	1,356,400
Non-QM loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	4,540,553	4,291,086
Legacy RPL/NPL loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,061,802	1,082,549
Other Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	53,137	52,073
Estimated Fair Value
Accounts, Notes, Loans and Financing Receivable [Line Items]
2025	421,411
2024	1,753,390
2023	1,557,785
2022	1,430,655
2021	1,714,829
Prior	653,997
Total	7,532,067
Estimated Fair Value \| Business purpose loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	3,019,344	3,265,548
Estimated Fair Value \| Business purpose loans \| Single-family transitional loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
2025	78,535
2024	504,716
2023	285,773
2022	92,575
2021	13,788
Prior	38
Total	975,425
Estimated Fair Value \| Business purpose loans \| Multifamily transitional loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
2025	0
2024	78,558
2023	401,209
2022	249,335
2021	105,947
Prior	0
Total	835,049	938,926
Estimated Fair Value \| Business purpose loans \| Single-family rental loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
2025	37,848
2024	43,127
2023	234,439
2022	525,711
2021	359,963
Prior	7,782
Total	1,208,870	1,248,197
Estimated Fair Value \| Non-QM loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
2025	305,028
2024	1,126,989
2023	636,364
2022	563,034
2021	1,181,994
Prior	31,621
Total	3,845,030	3,568,694
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	614,556
Total	614,556	624,895
Estimated Fair Value \| Other Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
2025	0
2024	0
2023	0
2022	0
2021	53,137
Prior	0
Total	$ 53,137	$ 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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