Expected Loss to be Paid (Recovered) - Key Assumptions in Base Case Expected Loss First Lien RMBS (Details) - U.S. - RMBS	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Schedule of Expected Losses to be Paid [Line Items]
Initial loss severity		50.00%
Base Scenario \| First Lien
Schedule of Expected Losses to be Paid [Line Items]
Future recovery for deferred principal balances	50.00%	30.00%
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%
Liquidation rates	20.00%	20.00%
Maximum
Schedule of Expected Losses to be Paid [Line Items]
Plateau CDR	8.80%	10.00%
Final CDR	0.40%	0.50%
Initial loss severity	50.00%
Liquidation rates	50.00%	65.00%
Weighted Average
Schedule of Expected Losses to be Paid [Line Items]
Plateau CDR	3.40%	4.20%
Final CDR	0.20%	0.20%
Initial loss severity	43.10%

Guarantor Obligations, Projected Loss Assumption, Deferred Loan Balances to be Recovered, Percent

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[Line Items] for Schedule of Expected Losses to be Paid [Table]

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