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Residential Whole Loans - Additional Credit Related Information (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2022 | Jun. 30, 2022 | Mar. 31, 2022 | Sep. 30, 2021 | Jun. 30, 2021 | Mar. 31, 2021 | Sep. 30, 2022 | Dec. 31, 2021
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
2022 | $ 0 |  |  |  |  |  | $ 0 |
2021 | 65,903 |  |  |  |  |  | 65,903 |
2020 | 248,562 |  |  |  |  |  | 248,562 |
2019 | 675,984 |  |  |  |  |  | 675,984 |
2018 | 319,020 |  |  |  |  |  | 319,020 |
Prior | 605,808 |  |  |  |  |  | 605,808 |
Residential whole loans, total or weighted average | 1,915,277 |  |  |  |  |  | 1,915,277 |
Gross write-offs, 2020 |  |  |  |  |  |  | 92 |
Gross write-offs, 2019 |  |  |  |  |  |  | 522 |
Gross write-offs, 2018 |  |  |  |  |  |  | 160 |
Gross write-offs, prior |  |  |  |  |  |  | 391 |
Nine Months Ended September 30, 2022 Gross write-offs | 282 | $ 360 | $ 523 | $ 533 | $ 400 | $ 1,217 | $ 1,165 |
Ratio Loan-To-Value |  |  |  |  |  |  | 80.00% |
Debt-to-Value Ratio, Less than 80 Percent |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
2022 | 0 |  |  |  |  |  | $ 0 |
2021 | 63,768 |  |  |  |  |  | 63,768 |
2020 | 233,777 |  |  |  |  |  | 233,777 |
2019 | 661,427 |  |  |  |  |  | 661,427 |
2018 | 308,592 |  |  |  |  |  | 308,592 |
Prior | 503,327 |  |  |  |  |  | 503,327 |
Residential whole loans, total or weighted average | 1,770,891 |  |  |  |  |  | 1,770,891 |
Debt-to-Value Ratio, 81 to 100 Percent |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
2022 | 0 |  |  |  |  |  | 0 |
2021 | 2,135 |  |  |  |  |  | 2,135 |
2020 | 14,785 |  |  |  |  |  | 14,785 |
2019 | 14,557 |  |  |  |  |  | 14,557 |
2018 | 10,428 |  |  |  |  |  | 10,428 |
Prior | 102,481 |  |  |  |  |  | 102,481 |
Residential whole loans, total or weighted average | 144,386 |  |  |  |  |  | 144,386 |
Non-QM loans |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
2022 | 0 |  |  |  |  |  | 0 |
2021 | 50,044 |  |  |  |  |  | 50,044 |
2020 | 213,889 |  |  |  |  |  | 213,889 |
2019 | 483,733 |  |  |  |  |  | 483,733 |
2018 | 252,698 |  |  |  |  |  | 252,698 |
Prior | 30,142 |  |  |  |  |  | 30,142 |
Residential whole loans, total or weighted average | 1,030,506 |  |  |  |  |  | 1,030,506 |
Gross write-offs, 2018 |  |  |  |  |  |  | 51 |
Nine Months Ended September 30, 2022 Gross write-offs |  |  |  |  |  |  | 51 |
Non-QM loans | Debt-to-Value Ratio, Less than 80 Percent |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
2022 | 0 |  |  |  |  |  | 0 |
2021 | 47,909 |  |  |  |  |  | 47,909 |
2020 | 199,510 |  |  |  |  |  | 199,510 |
2019 | 476,591 |  |  |  |  |  | 476,591 |
2018 | 245,908 |  |  |  |  |  | 245,908 |
Prior | 29,082 |  |  |  |  |  | 29,082 |
Residential whole loans, total or weighted average | 999,000 |  |  |  |  |  | 999,000 |
Non-QM loans | Debt-to-Value Ratio, 81 to 100 Percent |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
2022 | 0 |  |  |  |  |  | 0 |
2021 | 2,135 |  |  |  |  |  | 2,135 |
2020 | 14,379 |  |  |  |  |  | 14,379 |
2019 | 7,142 |  |  |  |  |  | 7,142 |
2018 | 6,790 |  |  |  |  |  | 6,790 |
Prior | 1,060 |  |  |  |  |  | 1,060 |
Residential whole loans, total or weighted average | 31,506 |  |  |  |  |  | $ 31,506 |
Non-QM loans | Settled Whole Loans |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
Ratio Loan-To-Value |  |  |  |  |  |  | 65.00% | 66.00%
Residential transition loans |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
2022 | 0 |  |  |  |  |  | $ 0 |
2021 | 2,037 |  |  |  |  |  | 2,037 |
2020 | 7,698 |  |  |  |  |  | 7,698 |
2019 | 61,664 |  |  |  |  |  | 61,664 |
2018 | 16,617 |  |  |  |  |  | 16,617 |
Prior | 4,746 |  |  |  |  |  | 4,746 |
Residential whole loans, total or weighted average | 92,762 |  |  |  |  |  | 92,762 |
Gross write-offs, 2020 |  |  |  |  |  |  | 92 |
Gross write-offs, 2019 |  |  |  |  |  |  | 317 |
Gross write-offs, 2018 |  |  |  |  |  |  | 41 |
Nine Months Ended September 30, 2022 Gross write-offs |  |  |  |  |  |  | 450 |
Residential transition loans | Debt-to-Value Ratio, Less than 80 Percent |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
2022 | 0 |  |  |  |  |  | 0 |
2021 | 2,037 |  |  |  |  |  | 2,037 |
2020 | 7,698 |  |  |  |  |  | 7,698 |
2019 | 57,070 |  |  |  |  |  | 57,070 |
2018 | 13,065 |  |  |  |  |  | 13,065 |
Prior | 3,047 |  |  |  |  |  | 3,047 |
Residential whole loans, total or weighted average | 82,917 |  |  |  |  |  | 82,917 |
Residential transition loans | Debt-to-Value Ratio, 81 to 100 Percent |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
2022 | 0 |  |  |  |  |  | 0 |
2021 | 0 |  |  |  |  |  | 0 |
2020 | 0 |  |  |  |  |  | 0 |
2019 | 4,594 |  |  |  |  |  | 4,594 |
2018 | 3,552 |  |  |  |  |  | 3,552 |
Prior | 1,699 |  |  |  |  |  | 1,699 |
Residential whole loans, total or weighted average | 9,845 |  |  |  |  |  | $ 9,845 |
Residential transition loans | Settled Whole Loans |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
Ratio Loan-To-Value |  |  |  |  |  |  | 66.00% | 67.00%
Single-family rental loans |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
2022 | 0 |  |  |  |  |  | $ 0 |
2021 | 13,822 |  |  |  |  |  | 13,822 |
2020 | 26,975 |  |  |  |  |  | 26,975 |
2019 | 130,587 |  |  |  |  |  | 130,587 |
2018 | 49,705 |  |  |  |  |  | 49,705 |
Prior | 3,213 |  |  |  |  |  | 3,213 |
Residential whole loans, total or weighted average | 224,302 |  |  |  |  |  | 224,302 |
Gross write-offs, 2019 |  |  |  |  |  |  | 205 |
Gross write-offs, 2018 |  |  |  |  |  |  | 68 |
Nine Months Ended September 30, 2022 Gross write-offs |  |  |  |  |  |  | 273 |
Single-family rental loans | Debt-to-Value Ratio, Less than 80 Percent |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
2022 | 0 |  |  |  |  |  | 0 |
2021 | 13,822 |  |  |  |  |  | 13,822 |
2020 | 26,569 |  |  |  |  |  | 26,569 |
2019 | 127,766 |  |  |  |  |  | 127,766 |
2018 | 49,619 |  |  |  |  |  | 49,619 |
Prior | 3,213 |  |  |  |  |  | 3,213 |
Residential whole loans, total or weighted average | 220,989 |  |  |  |  |  | 220,989 |
Single-family rental loans | Debt-to-Value Ratio, 81 to 100 Percent |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
2022 | 0 |  |  |  |  |  | 0 |
2021 | 0 |  |  |  |  |  | 0 |
2020 | 406 |  |  |  |  |  | 406 |
2019 | 2,821 |  |  |  |  |  | 2,821 |
2018 | 86 |  |  |  |  |  | 86 |
Prior | 0 |  |  |  |  |  | 0 |
Residential whole loans, total or weighted average | 3,313 |  |  |  |  |  | $ 3,313 |
Single-family rental loans | Settled Whole Loans |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
Ratio Loan-To-Value |  |  |  |  |  |  | 69.00% | 70.00%
Seasoned performing loans |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
2022 | 0 |  |  |  |  |  | $ 0 |
2021 | 0 |  |  |  |  |  | 0 |
2020 | 0 |  |  |  |  |  | 0 |
2019 | 0 |  |  |  |  |  | 0 |
2018 | 0 |  |  |  |  |  | 0 |
Prior | 87,028 |  |  |  |  |  | 87,028 |
Residential whole loans, total or weighted average | 87,028 |  |  |  |  |  | 87,028 |
Seasoned performing loans | Debt-to-Value Ratio, Less than 80 Percent |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
2022 | 0 |  |  |  |  |  | 0 |
2021 | 0 |  |  |  |  |  | 0 |
2020 | 0 |  |  |  |  |  | 0 |
2019 | 0 |  |  |  |  |  | 0 |
2018 | 0 |  |  |  |  |  | 0 |
Prior | 84,120 |  |  |  |  |  | 84,120 |
Residential whole loans, total or weighted average | 84,120 |  |  |  |  |  | 84,120 |
Seasoned performing loans | Debt-to-Value Ratio, 81 to 100 Percent |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
2022 | 0 |  |  |  |  |  | 0 |
2021 | 0 |  |  |  |  |  | 0 |
2020 | 0 |  |  |  |  |  | 0 |
2019 | 0 |  |  |  |  |  | 0 |
2018 | 0 |  |  |  |  |  | 0 |
Prior | 2,908 |  |  |  |  |  | 2,908 |
Residential whole loans, total or weighted average | 2,908 |  |  |  |  |  | $ 2,908 |
Seasoned performing loans | Settled Whole Loans |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
Ratio Loan-To-Value |  |  |  |  |  |  | 30.00% | 37.00%
Purchased Credit Deteriorated Loans |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
2022 | 0 |  |  |  |  |  | $ 0 |
2021 | 0 |  |  |  |  |  | 0 |
2020 | 0 |  |  |  |  |  | 0 |
2019 | 0 |  |  |  |  |  | 0 |
2018 | 0 |  |  |  |  |  | 0 |
Prior | 480,679 |  |  |  |  |  | 480,679 |
Residential whole loans, total or weighted average | 480,679 |  |  |  |  |  | 480,679 | $ 547,772
Gross write-offs, prior |  |  |  |  |  |  | 391 |
Nine Months Ended September 30, 2022 Gross write-offs |  |  |  |  |  |  | 391 |
Purchased Credit Deteriorated Loans | Debt-to-Value Ratio, Less than 80 Percent |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
2022 | 0 |  |  |  |  |  | 0 |
2021 | 0 |  |  |  |  |  | 0 |
2020 | 0 |  |  |  |  |  | 0 |
2019 | 0 |  |  |  |  |  | 0 |
2018 | 0 |  |  |  |  |  | 0 |
Prior | 383,865 |  |  |  |  |  | 383,865 |
Residential whole loans, total or weighted average | 383,865 |  |  |  |  |  | 383,865 |
Purchased Credit Deteriorated Loans | Debt-to-Value Ratio, 81 to 100 Percent |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
2022 | 0 |  |  |  |  |  | 0 |
2021 | 0 |  |  |  |  |  | 0 |
2020 | 0 |  |  |  |  |  | 0 |
2019 | 0 |  |  |  |  |  | 0 |
2018 | 0 |  |  |  |  |  | 0 |
Prior | 96,814 |  |  |  |  |  | 96,814 |
Residential whole loans, total or weighted average | $ 96,814 |  |  |  |  |  | $ 96,814 |
Certain rehabilitation loans | Settled Whole Loans |  |  |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |  |  |
Ratio Loan-To-Value |  |  |  |  |  |  | 71.00% | 71.00%

X
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- Definition Financing Receivable, Originated Three Years before Latest Fiscal Year, Gross Write-Offs + References No definition available. + Details
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- Definition The LTV of which the Company has assessed its residential whole loans at carrying value will have a higher likelihood of default than newly originated mortgage loans + References No definition available. + Details
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