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Expected Loss to be Paid (Recovered) - Key Assumptions in Base Scenario Expected Loss First Lien RMBS (Details) - RMBS - United States | 3 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2025 | Dec. 31, 2024
Base Scenario | First Lien |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
Percent of deferred loan balances to be recovered | 50.00% | 50.00%
Home Equity Line of Credit |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
Initial loss severity | 98.00% | 98.00%
Projected future recoveries on previously charged-off loans | 60.00% | 50.00%
Minimum |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
Plateau CDR | 0.00% | 0.00%
Final CDR | 0.00% | 0.00%
Initial loss severity | 40.00% | 40.00%
Liquidation rate | 20.00% | 20.00%
Minimum | Home Equity Line of Credit |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
Plateau CDR | 0.10% | 0.00%
Final CDR | 0.00% | 0.00%
Liquidation rate | 20.00% | 20.00%
Maximum |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
Plateau CDR | 9.20% | 8.80%
Final CDR | 0.50% | 0.40%
Initial loss severity | 50.00% | 50.00%
Liquidation rate | 50.00% | 50.00%
Maximum | Home Equity Line of Credit |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
Plateau CDR | 10.70% | 5.60%
Final CDR | 0.50% | 0.30%
Liquidation rate | 55.00% | 55.00%
Weighted Average |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
Plateau CDR | 3.20% | 3.40%
Final CDR | 0.20% | 0.20%
Initial loss severity | 43.00% | 43.10%
Weighted Average | Home Equity Line of Credit |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
Plateau CDR | 2.20% | 2.20%
Final CDR | 0.10% | 0.10%

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