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Residential Whole Loans (Additional Credit Related Information) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2021 | Mar. 31, 2021 | Jun. 30, 2020 | Mar. 31, 2020 | Jun. 30, 2021 | Dec. 31, 2020
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
2021 | $ 112,496 |  |  |  | $ 112,496 |
2020 | 487,950 |  |  |  | 487,950 |
2019 | 1,420,099 |  |  |  | 1,420,099 |
2018 | 646,181 |  |  |  | 646,181 |
2017 | 71,308 |  |  |  | 71,308 |
Prior | 732,351 |  |  |  | 732,351 |
Residential whole loans, at carrying value, total or weighted average | 3,470,385 |  |  |  | 3,470,385 |
Gross write-offs, 2020 |  |  |  |  | 0 |
Gross write-offs, 2019 |  |  |  |  | 1,052 |
Gross write-offs, 2018 |  |  |  |  | 223 |
Gross write-offs, 2017 |  |  |  |  | 20 |
Gross write-offs, prior |  |  |  |  | 322 |
Six Months Ended June 30, 2021 Gross write-offs | 400 | $ 1,217 | $ 627 | $ 647 | 1,617 |
Net write-offs, 2020 |  |  |  |  | 0 |
Net write-offs, 2019 |  |  |  |  | 1,052 |
Net write-offs, 2018 |  |  |  |  | 223 |
Net write-offs, 2017 |  |  |  |  | 20 |
Net write-offs |  |  |  |  | 322 |
Total Recoveries |  |  |  |  | 0 |
Six Months Ended June 30, 2021 Net write-offs |  |  |  |  | $ 1,617 |
Ratio Loan-To-Value |  |  |  |  | 80.00% |
Debt-to-Value Ratio, Less than 80 Percent |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
2021 | 108,290 |  |  |  | $ 108,290 |
2020 | 448,035 |  |  |  | 448,035 |
2019 | 1,393,049 |  |  |  | 1,393,049 |
2018 | 629,509 |  |  |  | 629,509 |
2017 | 65,166 |  |  |  | 65,166 |
Prior | 553,013 |  |  |  | 553,013 |
Residential whole loans, at carrying value, total or weighted average | 3,197,062 |  |  |  | 3,197,062 |
Debt-to-Value Ratio, 81 to 100 Percent |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
2021 | 4,206 |  |  |  | 4,206 |
2020 | 39,915 |  |  |  | 39,915 |
2019 | 27,050 |  |  |  | 27,050 |
2018 | 16,672 |  |  |  | 16,672 |
2017 | 6,142 |  |  |  | 6,142 |
Prior | 179,338 |  |  |  | 179,338 |
Residential whole loans, at carrying value, total or weighted average | 273,323 |  |  |  | 273,323 |
Non-QM loans |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
2021 | 82,836 |  |  |  | 82,836 |
2020 | 411,818 |  |  |  | 411,818 |
2019 | 910,442 |  |  |  | 910,442 |
2018 | 497,230 |  |  |  | 497,230 |
2017 | 53,077 |  |  |  | 53,077 |
Prior | 5,452 |  |  |  | 5,452 |
Residential whole loans, at carrying value, total or weighted average | 1,960,855 |  |  |  | 1,960,855 |
Gross write-offs, 2019 |  |  |  |  | 0 |
Gross write-offs, 2018 |  |  |  |  | 37 |
Six Months Ended June 30, 2021 Gross write-offs |  |  |  |  | 37 |
Net write-offs, 2019 |  |  |  |  | 0 |
Net write-offs, 2018 |  |  |  |  | 37 |
Six Months Ended June 30, 2021 Net write-offs |  |  |  |  | 37 |
Non-QM loans | Debt-to-Value Ratio, Less than 80 Percent |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
2021 | 78,630 |  |  |  | 78,630 |
2020 | 372,416 |  |  |  | 372,416 |
2019 | 890,461 |  |  |  | 890,461 |
2018 | 480,645 |  |  |  | 480,645 |
2017 | 48,635 |  |  |  | 48,635 |
Prior | 5,301 |  |  |  | 5,301 |
Residential whole loans, at carrying value, total or weighted average | 1,876,088 |  |  |  | 1,876,088 |
Non-QM loans | Debt-to-Value Ratio, 81 to 100 Percent |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
2021 | 4,206 |  |  |  | 4,206 |
2020 | 39,402 |  |  |  | 39,402 |
2019 | 19,981 |  |  |  | 19,981 |
2018 | 16,585 |  |  |  | 16,585 |
2017 | 4,442 |  |  |  | 4,442 |
Prior | 151 |  |  |  | 151 |
Residential whole loans, at carrying value, total or weighted average | 84,767 |  |  |  | 84,767 |
Rehabilitation loans |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
2021 | 14,042 |  |  |  | 14,042 |
2020 | 37,161 |  |  |  | 37,161 |
2019 | 263,370 |  |  |  | 263,370 |
2018 | 44,333 |  |  |  | 44,333 |
2017 | 5,557 |  |  |  | 5,557 |
Prior | 0 |  |  |  | 0 |
Residential whole loans, at carrying value, total or weighted average | 364,463 |  |  |  | 364,463 |
Gross write-offs, 2020 |  |  |  |  | 0 |
Gross write-offs, 2019 |  |  |  |  | 1,052 |
Gross write-offs, 2018 |  |  |  |  | 186 |
Gross write-offs, 2017 |  |  |  |  | 20 |
Gross write-offs, prior |  |  |  |  | 0 |
Six Months Ended June 30, 2021 Gross write-offs |  |  |  |  | 1,258 |
Net write-offs, 2020 |  |  |  |  | 0 |
Net write-offs, 2019 |  |  |  |  | 1,052 |
Net write-offs, 2018 |  |  |  |  | 186 |
Net write-offs, 2017 |  |  |  |  | 20 |
Net write-offs |  |  |  |  | 0 |
Six Months Ended June 30, 2021 Net write-offs |  |  |  |  | 1,258 |
Rehabilitation loans | Debt-to-Value Ratio, Less than 80 Percent |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
2021 | 14,042 |  |  |  | 14,042 |
2020 | 37,161 |  |  |  | 37,161 |
2019 | 262,144 |  |  |  | 262,144 |
2018 | 44,333 |  |  |  | 44,333 |
2017 | 3,857 |  |  |  | 3,857 |
Prior | 0 |  |  |  | 0 |
Residential whole loans, at carrying value, total or weighted average | 361,537 |  |  |  | 361,537 |
Rehabilitation loans | Debt-to-Value Ratio, 81 to 100 Percent |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
2021 | 0 |  |  |  | 0 |
2020 | 0 |  |  |  | 0 |
2019 | 1,226 |  |  |  | 1,226 |
2018 | 0 |  |  |  | 0 |
2017 | 1,700 |  |  |  | 1,700 |
Prior | 0 |  |  |  | 0 |
Residential whole loans, at carrying value, total or weighted average | 2,926 |  |  |  | 2,926 |
Single-family rental loans |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
2021 | 15,618 |  |  |  | 15,618 |
2020 | 38,971 |  |  |  | 38,971 |
2019 | 246,287 |  |  |  | 246,287 |
2018 | 104,618 |  |  |  | 104,618 |
2017 | 12,050 |  |  |  | 12,050 |
Prior | 0 |  |  |  | 0 |
Residential whole loans, at carrying value, total or weighted average | 417,544 |  |  |  | 417,544 |
Single-family rental loans | Debt-to-Value Ratio, Less than 80 Percent |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
2021 | 15,618 |  |  |  | 15,618 |
2020 | 38,458 |  |  |  | 38,458 |
2019 | 240,444 |  |  |  | 240,444 |
2018 | 104,531 |  |  |  | 104,531 |
2017 | 12,050 |  |  |  | 12,050 |
Prior | 0 |  |  |  | 0 |
Residential whole loans, at carrying value, total or weighted average | 411,101 |  |  |  | 411,101 |
Single-family rental loans | Debt-to-Value Ratio, 81 to 100 Percent |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
2021 | 0 |  |  |  | 0 |
2020 | 513 |  |  |  | 513 |
2019 | 5,843 |  |  |  | 5,843 |
2018 | 87 |  |  |  | 87 |
2017 | 0 |  |  |  | 0 |
Prior | 0 |  |  |  | 0 |
Residential whole loans, at carrying value, total or weighted average | 6,443 |  |  |  | 6,443 |
Seasoned performing loans |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
2021 | 0 |  |  |  | 0 |
2020 | 0 |  |  |  | 0 |
2019 | 0 |  |  |  | 0 |
2018 | 0 |  |  |  | 0 |
2017 | 0 |  |  |  | 0 |
Prior | 118,366 |  |  |  | 118,366 |
Residential whole loans, at carrying value, total or weighted average | 118,366 |  |  |  | 118,366 |
Seasoned performing loans | Debt-to-Value Ratio, Less than 80 Percent |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
2021 | 0 |  |  |  | 0 |
2020 | 0 |  |  |  | 0 |
2019 | 0 |  |  |  | 0 |
2018 | 0 |  |  |  | 0 |
2017 | 0 |  |  |  | 0 |
Prior | 112,734 |  |  |  | 112,734 |
Residential whole loans, at carrying value, total or weighted average | 112,734 |  |  |  | 112,734 |
Seasoned performing loans | Debt-to-Value Ratio, 81 to 100 Percent |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
2021 | 0 |  |  |  | 0 |
2020 | 0 |  |  |  | 0 |
2019 | 0 |  |  |  | 0 |
2018 | 0 |  |  |  | 0 |
2017 | 0 |  |  |  | 0 |
Prior | 5,632 |  |  |  | 5,632 |
Residential whole loans, at carrying value, total or weighted average | 5,632 |  |  |  | 5,632 |
Purchased credit deteriorated loans |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
2021 | 0 |  |  |  | 0 |
2020 | 0 |  |  |  | 0 |
2019 | 0 |  |  |  | 0 |
2018 | 0 |  |  |  | 0 |
2017 | 624 |  |  |  | 624 |
Prior | 608,533 |  |  |  | 608,533 |
Residential whole loans, at carrying value, total or weighted average | 609,157 |  |  |  | 609,157 | $ 673,708
Gross write-offs, prior |  |  |  |  | 322 |
Six Months Ended June 30, 2021 Gross write-offs |  |  |  |  | 322 |
Net write-offs |  |  |  |  | 322 |
Total Recoveries |  |  |  |  | 0 |
Six Months Ended June 30, 2021 Net write-offs |  |  |  |  | 322 |
Purchased credit deteriorated loans | Debt-to-Value Ratio, Less than 80 Percent |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
2021 | 0 |  |  |  | 0 |
2020 | 0 |  |  |  | 0 |
2019 | 0 |  |  |  | 0 |
2018 | 0 |  |  |  | 0 |
2017 | 624 |  |  |  | 624 |
Prior | 434,978 |  |  |  | 434,978 |
Residential whole loans, at carrying value, total or weighted average | 435,602 |  |  |  | 435,602 |
Purchased credit deteriorated loans | Debt-to-Value Ratio, 81 to 100 Percent |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
2021 | 0 |  |  |  | 0 |
2020 | 0 |  |  |  | 0 |
2019 | 0 |  |  |  | 0 |
2018 | 0 |  |  |  | 0 |
2017 | 0 |  |  |  | 0 |
Prior | 173,555 |  |  |  | 173,555 |
Residential whole loans, at carrying value, total or weighted average | 173,555 |  |  |  | 173,555 |
Settled Whole Loans | Non-QM loans |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Purchased performing loans | 1,948,763 |  |  |  | $ 1,948,763 | $ 2,336,117
Ratio Loan-To-Value |  |  |  |  | 63.00% | 64.00%
Settled Whole Loans | Rehabilitation loans |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Purchased performing loans | 352,859 |  |  |  | $ 352,859 | $ 563,430
Ratio Loan-To-Value |  |  |  |  | 65.00% | 63.00%
Settled Whole Loans | Single-family rental loans |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Purchased performing loans | 415,184 |  |  |  | $ 415,184 | $ 442,456
Ratio Loan-To-Value |  |  |  |  | 69.00% | 70.00%
Settled Whole Loans | Seasoned performing loans |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Purchased performing loans | 118,309 |  |  |  | $ 118,309 | $ 136,157
Ratio Loan-To-Value |  |  |  |  | 39.00% | 40.00%
Settled Whole Loans | Certain rehabilitation loans |  |  |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |  |  |
Purchased performing loans | $ 134,200 |  |  |  | $ 134,200 | $ 189,900
Ratio Loan-To-Value |  |  |  |  | 69.00% | 69.00%

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