Residential Whole Loans - Vintage Information Regarding Residential Whole Loans (Details) - Residential whole loan - USD ($) $ in Thousands	Sep. 30, 2024	Dec. 31, 2023
Business purpose loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	$ 3,684,042	$ 3,996,292
Business purpose loans \| Multifamily transitional loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,058,079	1,168,297
Business purpose loans \| Single-family rental loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,473,062	1,634,796
Non-QM loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	4,172,797	3,805,577
Legacy RPL/NPL loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	1,125,280	1,204,095
Other loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	55,909	55,779
Estimated Fair Value
Accounts, Notes, Loans and Financing Receivable [Line Items]
2024	1,317,940
2023	1,998,121
2022	1,670,934
2021	1,985,681
2020	9,044
Prior	693,021
Total	7,674,741
Estimated Fair Value \| Business purpose loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total	3,539,507	3,788,612
Estimated Fair Value \| Business purpose loans \| Single-family transitional loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
2024	455,519
2023	497,487
2022	149,391
2021	24,669
2020	407
Prior	46
Total	1,127,519
Estimated Fair Value \| Business purpose loans \| Multifamily transitional loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
2024	86,877
2023	518,096
2022	322,220
2021	130,886
2020	0
Prior	0
Total	1,058,079	1,168,297
Estimated Fair Value \| Business purpose loans \| Single-family rental loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
2024	138,611
2023	247,698
2022	573,362
2021	385,558
2020	8,399
Prior	281
Total	1,353,909	1,462,583
Estimated Fair Value \| Non-QM loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
2024	636,933
2023	734,840
2022	625,961
2021	1,388,659
2020	238
Prior	34,616
Total	3,421,247	2,961,693
Estimated Fair Value \| Legacy RPL/NPL loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
2024	0
2023	0
2022	0
2021	0
2020	0
Prior	658,078
Total	658,078	705,424
Estimated Fair Value \| Other loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
2024	0
2023	0
2022	0
2021	55,909
2020	0
Prior	0
Total	$ 55,909	$ 55,779

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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