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Residential Whole Loans (Additional Credit Related Information) (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Mar. 31, 2021 | Mar. 31, 2020 | Sep. 30, 2020 | Dec. 31, 2020
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
2021 | $ 119,691 |  |  |
2020 | 546,721 |  |  |
2019 | 1,650,170 |  |  |
2018 | 751,683 |  |  |
2017 | 86,491 |  |  |
Prior | 777,544 |  |  |
Residential whole loans, at carrying value, total or weighted average | 3,932,300 |  |  |
Gross write-offs, 2020 | 0 |  |  |
Gross write-offs, 2019 | 991 |  |  |
Gross write-offs, 2018 | 12 |  |  |
Gross write-offs, prior | 214 |  |  |
Three Months Ended March 31, 2021 Gross write-offs | 1,217 | $ 647 |  |
Net write-offs, 2020 | 0 |  |  |
Net write-offs, 2019 | 991 |  |  |
Net write-offs, 2018 | 12 |  |  |
Net write-offs | 214 |  |  |
Total Recoveries | 0 |  |  |
Three Months Ended March 31, 2021 Net write-offs | 1,217 |  |  |
Purchased performing loans | $ 3,287,689 |  |  | $ 3,521,624
Ratio Loan-To-Value | 80.00% |  |  |
Debt-to-Value Ratio, Less than 80 Percent |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
2021 | $ 115,420 |  |  |
2020 | 502,632 |  |  |
2019 | 1,617,755 |  |  |
2018 | 732,372 |  |  |
2017 | 80,192 |  |  |
Prior | 551,316 |  |  |
Residential whole loans, at carrying value, total or weighted average | 3,599,687 |  |  |
Debt-to-Value Ratio, 81 to 100 Percent |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
2021 | 4,271 |  |  |
2020 | 44,089 |  |  |
2019 | 32,415 |  |  |
2018 | 19,311 |  |  |
2017 | 6,299 |  |  |
Prior | 226,228 |  |  |
Residential whole loans, at carrying value, total or weighted average | 332,613 |  |  |
Non-QM Loans |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
2021 | 91,059 |  |  |
2020 | 463,139 |  |  |
2019 | 1,036,830 |  |  |
2018 | 579,713 |  |  |
2017 | 67,212 |  |  |
Prior | 5,491 |  |  |
Residential whole loans, at carrying value, total or weighted average | 2,243,444 |  |  |
Gross write-offs, 2019 | 0 |  |  |
Three Months Ended March 31, 2021 Gross write-offs | 0 |  |  |
Net write-offs, 2019 | 0 |  |  |
Three Months Ended March 31, 2021 Net write-offs | 0 |  |  |
Purchased performing loans | 2,243,444 |  |  | 2,357,185
Non-QM Loans | Debt-to-Value Ratio, Less than 80 Percent |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
2021 | 86,788 |  |  |
2020 | 419,564 |  |  |
2019 | 1,012,210 |  |  |
2018 | 560,489 |  |  |
2017 | 62,613 |  |  |
Prior | 5,340 |  |  |
Residential whole loans, at carrying value, total or weighted average | 2,147,004 |  |  |
Non-QM Loans | Debt-to-Value Ratio, 81 to 100 Percent |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
2021 | 4,271 |  |  |
2020 | 43,575 |  |  |
2019 | 24,620 |  |  |
2018 | 19,224 |  |  |
2017 | 4,599 |  |  |
Prior | 151 |  |  |
Residential whole loans, at carrying value, total or weighted average | 96,440 |  |  |
Rehabilitation loans |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
2021 | 12,867 |  |  |
2020 | 43,504 |  |  |
2019 | 343,355 |  |  |
2018 | 58,888 |  |  |
2017 | 5,771 |  |  |
Prior | 0 |  |  |
Residential whole loans, at carrying value, total or weighted average | 464,385 |  |  |
Gross write-offs, 2020 | 0 |  |  |
Gross write-offs, 2019 | 991 |  |  |
Gross write-offs, 2018 | 12 |  |  |
Gross write-offs, prior | 0 |  |  |
Three Months Ended March 31, 2021 Gross write-offs | 1,003 |  |  |
Net write-offs, 2020 | 0 |  |  |
Net write-offs, 2019 | 991 |  |  |
Net write-offs, 2018 | 12 |  |  |
Net write-offs | 0 |  |  |
Three Months Ended March 31, 2021 Net write-offs | 1,003 |  |  |
Purchased performing loans | 464,385 |  |  | 581,801
Rehabilitation loans | Debt-to-Value Ratio, Less than 80 Percent |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
2021 | 12,867 |  |  |
2020 | 43,504 |  |  |
2019 | 341,513 |  |  |
2018 | 58,888 |  |  |
2017 | 4,071 |  |  |
Prior | 0 |  |  |
Residential whole loans, at carrying value, total or weighted average | 460,843 |  |  |
Rehabilitation loans | Debt-to-Value Ratio, 81 to 100 Percent |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
2021 | 0 |  |  |
2020 | 0 |  |  |
2019 | 1,842 |  |  |
2018 | 0 |  |  |
2017 | 1,700 |  |  |
Prior | 0 |  |  |
Residential whole loans, at carrying value, total or weighted average | 3,542 |  |  |
Single-family rental loans |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
2021 | 15,765 |  |  |
2020 | 40,078 |  |  |
2019 | 269,985 |  |  |
2018 | 113,082 |  |  |
2017 | 12,881 |  |  |
Prior | 0 |  |  |
Residential whole loans, at carrying value, total or weighted average | 451,791 |  |  |
Purchased performing loans | 451,791 |  |  | 446,374
Single-family rental loans | Debt-to-Value Ratio, Less than 80 Percent |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
2021 | 15,765 |  |  |
2020 | 39,564 |  |  |
2019 | 264,032 |  |  |
2018 | 112,995 |  |  |
2017 | 12,881 |  |  |
Prior | 0 |  |  |
Residential whole loans, at carrying value, total or weighted average | 445,237 |  |  |
Single-family rental loans | Debt-to-Value Ratio, 81 to 100 Percent |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
2021 | 0 |  |  |
2020 | 514 |  |  |
2019 | 5,953 |  |  |
2018 | 87 |  |  |
2017 | 0 |  |  |
Prior | 0 |  |  |
Residential whole loans, at carrying value, total or weighted average | 6,554 |  |  |
Seasoned performing loans |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
2021 | 0 |  |  |
2020 | 0 |  |  |
2019 | 0 |  |  |
2018 | 0 |  |  |
2017 | 0 |  |  |
Prior | 128,069 |  |  |
Residential whole loans, at carrying value, total or weighted average | 128,069 |  |  |
Purchased performing loans | 128,069 |  |  | 136,264
Seasoned performing loans | Debt-to-Value Ratio, Less than 80 Percent |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
2021 | 0 |  |  |
2020 | 0 |  |  |
2019 | 0 |  |  |
2018 | 0 |  |  |
2017 | 0 |  |  |
Prior | 122,389 |  |  |
Residential whole loans, at carrying value, total or weighted average | 122,389 |  |  |
Seasoned performing loans | Debt-to-Value Ratio, 81 to 100 Percent |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
2021 | 0 |  |  |
2020 | 0 |  |  |
2019 | 0 |  |  |
2018 | 0 |  |  |
2017 | 0 |  |  |
Prior | 5,680 |  |  |
Residential whole loans, at carrying value, total or weighted average | 5,680 |  |  |
Purchased Credit Deteriorated Loans |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
2021 | 0 |  |  |
2020 | 0 |  |  |
2019 | 0 |  |  |
2018 | 0 |  |  |
2017 | 627 |  |  |
Prior | 643,984 |  |  |
Residential whole loans, at carrying value, total or weighted average | 644,611 |  |  |
Gross write-offs, prior | 214 |  |  |
Three Months Ended March 31, 2021 Gross write-offs | 214 |  |  |
Net write-offs | 214 |  |  |
Total Recoveries | 0 |  |  |
Three Months Ended March 31, 2021 Net write-offs | 214 |  |  |
Purchased Credit Deteriorated Loans | Debt-to-Value Ratio, Less than 80 Percent |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
2021 | 0 |  |  |
2020 | 0 |  |  |
2019 | 0 |  |  |
2018 | 0 |  |  |
2017 | 627 |  |  |
Prior | 423,587 |  |  |
Residential whole loans, at carrying value, total or weighted average | 424,214 |  |  |
Purchased Credit Deteriorated Loans | Debt-to-Value Ratio, 81 to 100 Percent |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
2021 | 0 |  |  |
2020 | 0 |  |  |
2019 | 0 |  |  |
2018 | 0 |  |  |
2017 | 0 |  |  |
Prior | 220,397 |  |  |
Residential whole loans, at carrying value, total or weighted average | 220,397 |  |  |
Settled Whole Loans | Non-QM Loans |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
Purchased performing loans | $ 2,228,899 |  |  | 2,336,117
Ratio Loan-To-Value | 64.00% |  | 64.00% |
Settled Whole Loans | Rehabilitation loans |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
Purchased performing loans | $ 450,717 |  |  | 563,430
Ratio Loan-To-Value | 64.00% |  | 63.00% |
Settled Whole Loans | Single-family rental loans |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
Purchased performing loans | $ 449,045 |  |  | 442,456
Ratio Loan-To-Value | 70.00% |  | 70.00% |
Settled Whole Loans | Seasoned performing loans |  |  |  |
Financing Receivable, Credit Quality Indicator [Line Items] |  |  |  |
Purchased performing loans | $ 128,003 |  |  | 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 | $ 151,700 |  |  | $ 189,900
Ratio Loan-To-Value | 68.00% |  | 69.00% |

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