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Beneficial Interests - Schedule of Beneficial Interest Assets and Liabilities (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |
--- | --- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024 | Dec. 31, 2024
Schedule Of Beneficial Interest [Line Items] |  |  |  |  |
Unpaid principal balance, asset | $ 5,109,569 |  | $ 5,109,569 |  | $ 4,157,750
Fair value, asset | 266,761 |  | 266,761 |  | 176,848
Fair value, liability | 10,500 |  | 10,500 |  | 10,100
Derivatives |  |  |  |  |
Schedule Of Beneficial Interest [Line Items] |  |  |  |  |
Unpaid principal balance, liability | 2,155,391 |  | 2,155,391 |  | 1,091,538
Fair value, liability | 10,532 |  | 10,532 |  | 10,089
Hybrid Instruments |  |  |  |  |
Schedule Of Beneficial Interest [Line Items] |  |  |  |  |
Unpaid principal balance, asset | 2,876,992 |  | 2,876,992 |  | 2,214,535
Fair value, asset | 254,230 |  | 254,230 |  | 168,091
Derivatives |  |  |  |  |
Schedule Of Beneficial Interest [Line Items] |  |  |  |  |
Unpaid principal balance, asset | 2,232,577 |  | 2,232,577 |  | 1,943,215
Fair value, asset | 12,531 |  | 12,531 |  | $ 8,757
Beneficial interests |  |  |  |  |
Schedule Of Beneficial Interest [Line Items] |  |  |  |  |
Fair value adjustments and realized gains (losses) on beneficial interests, net | $ (6,288) | $ (8,176) | $ 11,377 | $ (22,210) |

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