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Residential Whole Loans - Additional Credit Related Information (Details) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2024 | Mar. 31, 2023 | Dec. 31, 2023
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
2024 | $ 0 |  |
2023 | 0 |  |
2022 | 0 |  |
2021 | 51,752 |  |
2020 | 197,803 |  |
Prior | 1,234,815 |  |
Total | 1,484,370 |  |
Gross write-offs, 2023 | 0 |  |
Gross write-offs, 2022 | 0 |  |
Gross write-offs, 2021 | 0 |  |
Gross write-offs, 2020 | 0 |  |
Gross write-offs, 2019 | (59) |  |
Gross write-offs, prior | 438 |  |
Gross write-offs | $ 379 | $ 2,567 |
Ratio loan- to-value (as a percent) | 80.00% |  |
Debt-to-Value Ratio, Less Than 80 Percent |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
2024 | $ 0 |  |
2023 | 0 |  |
2022 | 0 |  |
2021 | 50,366 |  |
2020 | 187,226 |  |
Prior | 1,153,943 |  |
Total | 1,391,535 |  |
Debt-to-Value Ratio, Greater Than 80 Percent |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
2024 | 0 |  |
2023 | 0 |  |
2022 | 0 |  |
2021 | 1,386 |  |
2020 | 10,577 |  |
Prior | 80,872 |  |
Total | 92,835 |  |
Non-QM loans |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
2024 | 0 |  |
2023 | 0 |  |
2022 | 0 |  |
2021 | 43,735 |  |
2020 | 174,832 |  |
Prior | 598,050 |  |
Total | 816,617 |  |
Gross write-offs, 2023 | 0 |  |
Gross write-offs, 2022 | 0 |  |
Gross write-offs, 2021 | 0 |  |
Gross write-offs, 2020 | 0 |  |
Gross write-offs, 2019 | 0 |  |
Gross write-offs, prior | 0 |  |
Gross write-offs | $ 0 |  |
Non-QM loans | Settled Whole Loans |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
Ratio loan- to-value (as a percent) | 65.00% |  | 65.00%
Non-QM loans | Debt-to-Value Ratio, Less Than 80 Percent |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
2024 | $ 0 |  |
2023 | 0 |  |
2022 | 0 |  |
2021 | 42,349 |  |
2020 | 164,663 |  |
Prior | 591,730 |  |
Total | 798,742 |  |
Non-QM loans | Debt-to-Value Ratio, Greater Than 80 Percent |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
2024 | 0 |  |
2023 | 0 |  |
2022 | 0 |  |
2021 | 1,386 |  |
2020 | 10,169 |  |
Prior | 6,320 |  |
Total | 17,875 |  |
Transitional loans |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
2024 | 0 |  |
2023 | 0 |  |
2022 | 0 |  |
2021 | 156 |  |
2020 | 3,915 |  |
Prior | 25,027 |  |
Total | 29,098 |  |
Gross write-offs, 2023 | 0 |  |
Gross write-offs, 2022 | 0 |  |
Gross write-offs, 2021 | 0 |  |
Gross write-offs, 2020 | 0 |  |
Gross write-offs, 2019 | 0 |  |
Gross write-offs, prior | 416 |  |
Gross write-offs | $ 416 |  |
Transitional loans | Settled Whole Loans |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
Ratio loan- to-value (as a percent) | 64.00% |  | 64.00%
Transitional loans | Debt-to-Value Ratio, Less Than 80 Percent |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
2024 | $ 0 |  |
2023 | 0 |  |
2022 | 0 |  |
2021 | 156 |  |
2020 | 3,915 |  |
Prior | 25,027 |  |
Total | 29,098 |  |
Transitional loans | Debt-to-Value Ratio, Greater Than 80 Percent |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
2024 | 0 |  |
2023 | 0 |  |
2022 | 0 |  |
2021 | 0 |  |
2020 | 0 |  |
Prior | 0 |  |
Total | 0 |  |
Single-family rental loans |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
2024 | 0 |  |
2023 | 0 |  |
2022 | 0 |  |
2021 | 7,861 |  |
2020 | 19,056 |  |
Prior | 122,026 |  |
Total | 148,943 |  |
Gross write-offs, 2023 | 0 |  |
Gross write-offs, 2022 | 0 |  |
Gross write-offs, 2021 | 0 |  |
Gross write-offs, 2020 | 0 |  |
Gross write-offs, 2019 | (59) |  |
Gross write-offs, prior | 0 |  |
Gross write-offs | (59) |  |
Single-family rental loans | Debt-to-Value Ratio, Less Than 80 Percent |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
2024 | 0 |  |
2023 | 0 |  |
2022 | 0 |  |
2021 | 7,861 |  |
2020 | 18,648 |  |
Prior | 109,439 |  |
Total | 135,948 |  |
Single-family rental loans | Debt-to-Value Ratio, Greater Than 80 Percent |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
2024 | 0 |  |
2023 | 0 |  |
2022 | 0 |  |
2021 | 0 |  |
2020 | 408 |  |
Prior | 12,587 |  |
Total | 12,995 |  |
Seasoned performing loans |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
2024 | 0 |  |
2023 | 0 |  |
2022 | 0 |  |
2021 | 0 |  |
2020 | 0 |  |
Prior | 66,065 |  |
Total | 66,065 |  |
Gross write-offs, 2023 | 0 |  |
Gross write-offs, 2022 | 0 |  |
Gross write-offs, 2021 | 0 |  |
Gross write-offs, 2020 | 0 |  |
Gross write-offs, 2019 | 0 |  |
Gross write-offs, prior | 0 |  |
Gross write-offs | $ 0 |  |
Seasoned performing loans | Settled Whole Loans |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
Ratio loan- to-value (as a percent) | 28.00% |  | 28.00%
Seasoned performing loans | Debt-to-Value Ratio, Less Than 80 Percent |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
2024 | $ 0 |  |
2023 | 0 |  |
2022 | 0 |  |
2021 | 0 |  |
2020 | 0 |  |
Prior | 63,739 |  |
Total | 63,739 |  |
Seasoned performing loans | Debt-to-Value Ratio, Greater Than 80 Percent |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
2024 | 0 |  |
2023 | 0 |  |
2022 | 0 |  |
2021 | 0 |  |
2020 | 0 |  |
Prior | 2,326 |  |
Total | 2,326 |  |
Purchased credit deteriorated loans |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
2024 | 0 |  |
2023 | 0 |  |
2022 | 0 |  |
2021 | 0 |  |
2020 | 0 |  |
Prior | 423,647 |  |
Total | 423,647 |  | $ 429,726
Gross write-offs, 2023 | 0 |  |
Gross write-offs, 2022 | 0 |  |
Gross write-offs, 2021 | 0 |  |
Gross write-offs, 2020 | 0 |  |
Gross write-offs, 2019 | 0 |  |
Gross write-offs, prior | 22 |  |
Gross write-offs | 22 |  |
Purchased credit deteriorated loans | Debt-to-Value Ratio, Less Than 80 Percent |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
2024 | 0 |  |
2023 | 0 |  |
2022 | 0 |  |
2021 | 0 |  |
2020 | 0 |  |
Prior | 364,008 |  |
Total | 364,008 |  |
Purchased credit deteriorated loans | Debt-to-Value Ratio, Greater Than 80 Percent |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
2024 | 0 |  |
2023 | 0 |  |
2022 | 0 |  |
2021 | 0 |  |
2020 | 0 |  |
Prior | 59,639 |  |
Total | 59,639 |  |
Certain rehabilitation loans | Transitional Loans |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
Purchased performing loans | $ 608,900 |  | $ 551,300
Certain rehabilitation loans | Settled Whole Loans |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |
Ratio loan- to-value (as a percent) | 67.00% |  | 68.00%

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