Securitization Transactions (Schedule of Assets and Liabilities Attributable to Consolidated VIEs) (Details) - USD ($) $ in Thousands |
Sep. 30, 2021 |
Dec. 31, 2020 |
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|---|---|---|---|---|---|---|
| Variable Interest Entity [Line Items] | ||||||
| Other secured borrowings, at fair value | [1] | $ 872,306 | $ 754,921 | |||
| Loans, at fair value | [1],[2] | 1,996,529 | 1,453,480 | |||
| Real estate owned | [1],[2] | 37,002 | 23,598 | |||
| Investment related receivables | [1] | 97,721 | 49,317 | |||
| Residential mortgage loans | ||||||
| Variable Interest Entity [Line Items] | ||||||
| Loans, at fair value | 1,656,701 | 1,187,069 | ||||
| Consolidated Entities [Member] | Non-QM loan securitization | ||||||
| Variable Interest Entity [Line Items] | ||||||
| Other secured borrowings, at fair value | 872,306 | 754,921 | ||||
| Investment related receivables | 26,871 | 15,544 | ||||
| Consolidated Entities [Member] | Residential mortgage loans | Securitized loans [Member] | Non-QM loan securitization | ||||||
| Variable Interest Entity [Line Items] | ||||||
| Loans, at fair value | $ 917,275 | $ 801,343 | ||||
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