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Use of Special Purpose Entities and Variable Interest Entities (Narrative) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020
Variable Interest Entity [Line Items] |  |
Residential whole loans | $ 7,900,000 | $ 5,300,000
Senior Notes |  |
Variable Interest Entity [Line Items] |  |
Proceeds from issuance of debt | 2,400,000 | 1,300,000
Proceed from senior notes net of offering expenses and underwriting discount | 2,400,000 | 1,300,000
Asset-backed Securities, Securitized Loans and Receivables |  |
Variable Interest Entity [Line Items] |  |
Proceeds from issuance of debt | 3,682,082 | 1,853,408
Residential Whole Loans, Carrying Value | 3,000,000 | 1,800,000
Securitized debt | 2,700,000 | 1,500,000
Asset-backed Securities, Securitized Loans and Receivables | Other Assets |  |
Variable Interest Entity [Line Items] |  |
Real estate owned at fair value | $ 35,400 | $ 49,500

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