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v3.23.3

Use of Special Purpose Entities and Variable Interest Entities - Loan Securitization Transaction (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended | 12 Months Ended
--- | --- | --- | ---
Sep. 30, 2023 | Sep. 30, 2023 | Dec. 31, 2022
Variable Interest Entity [Line Items] |  |  |
Weighted average fixed rate for Senior Bonds issued | 4.18% | 4.18% | 3.70%
Senior Notes |  |  |
Variable Interest Entity [Line Items] |  |  |
Cash received | $ 534,800 | $ 1,400,000 |
Asset-backed Securities, Securitized Loans and Receivables |  |  |
Variable Interest Entity [Line Items] |  |  |
Aggregate unpaid principal balance of residential whole loans sold | 7,721,012 | 7,721,012 | $ 6,079,749
Outstanding amount of Senior Bonds, at carrying value | 801,360 | 801,360 | 922,220
Outstanding amount of Senior Bonds, at fair value | 3,531,576 | 3,531,576 | 2,435,370
Outstanding amount of Senior Bonds, total | $ 4,332,936 | $ 4,332,936 | $ 3,357,590
Weighted average fixed rate for Senior Bonds issued | 4.22% | 4.22% | 3.38%
Weighted average contractual maturity of Senior Bonds |  | 37 years | 38 years
Cash received |  | $ 6,637,607 | $ 5,286,305
Debt issuance cost | $ 1,700 | 1,700 | 2,900
Asset-backed Securities, Securitized Loans and Receivables | Senior Notes |  |  |
Variable Interest Entity [Line Items] |  |  |
Debt instrument, face amount | 6,699,921 | 6,699,921 | 5,333,090
Proceeds from Senior bond sold with Step up feature |  | $ 3,000,000 | 1,900,000
Asset-backed Securities, Securitized Loans and Receivables | Senior Notes | Minimum |  |  |
Variable Interest Entity [Line Items] |  |  |
Debt instrument, basis spread on variable rate (in percent) |  | 1.00% |
Debt instrument, coupon step-up period |  | 24 months |
Asset-backed Securities, Securitized Loans and Receivables | Senior Notes | Median |  |  |
Variable Interest Entity [Line Items] |  |  |
Debt instrument, basis spread on variable rate (in percent) |  | 2.00% |
Asset-backed Securities, Securitized Loans and Receivables | Senior Notes | Maximum |  |  |
Variable Interest Entity [Line Items] |  |  |
Debt instrument, basis spread on variable rate (in percent) |  | 3.00% |
Debt instrument, coupon step-up period |  | 48 months |
Asset-backed Securities, Securitized Loans and Receivables | Senior Support Certificates |  |  |
Variable Interest Entity [Line Items] |  |  |
Debt instrument, face amount | $ 986,585 | $ 986,585 | $ 715,640

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