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Expected Loss to be Paid (Recovered) - Key Assumptions in Base Case Expected Loss First Lien RMBS (Details) - U.S. - RMBS | Dec. 31, 2023 | Dec. 31, 2022
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Alt-A |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
Initial loss severity | 50.00% | 50.00%
Alt-A | Minimum |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
CDR plateau | 1.40% | 1.60%
Final CDR | 0.10% | 0.10%
Alt-A | Maximum |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
CDR plateau | 9.00% | 11.50%
Final CDR | 0.40% | 0.60%
Alt-A | Weighted Average |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
CDR plateau | 3.60% | 5.10%
Final CDR | 0.20% | 0.30%
Adjustable Rate Residential Mortgage [Member] |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
Initial loss severity | 50.00% | 50.00%
Adjustable Rate Residential Mortgage [Member] | Minimum |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
CDR plateau | 0.00% | 2.00%
Final CDR | 0.00% | 0.10%
Adjustable Rate Residential Mortgage [Member] | Maximum |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
CDR plateau | 8.90% | 7.70%
Final CDR | 0.40% | 0.40%
Adjustable Rate Residential Mortgage [Member] | Weighted Average |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
CDR plateau | 3.30% | 4.30%
Final CDR | 0.20% | 0.20%
Financing Receivable, Subprime [Member] |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
Initial loss severity | 50.00% | 50.00%
Financing Receivable, Subprime [Member] | Minimum |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
CDR plateau | 0.30% | 2.70%
Final CDR | 0.00% | 0.10%
Financing Receivable, Subprime [Member] | Maximum |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
CDR plateau | 10.00% | 9.70%
Final CDR | 0.50% | 0.50%
Financing Receivable, Subprime [Member] | Weighted Average |  |
Schedule of Expected Losses to be Paid [Line Items] |  |
CDR plateau | 4.40% | 5.60%
Final CDR | 0.20% | 0.30%

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