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Expected Loss to be Paid (Recovered) - Net Expected Loss to be Paid After Net Expected Recoveries for Breaches of R&W Rollforward (Details) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2026 | Mar. 31, 2025 | Dec. 31, 2025
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |
Net expected loss to be paid (recovered), beginning of period | $ 101 | $ 106 | $ 106
Accretion of discount | 2 | 1 |
Changes in discount rates | (4) | 5 |
Changes in timing and assumptions | 46 | (21) |
Total economic loss development (benefit) | 44 | (15) |
Net (paid) recovered losses | (4) | 59 |
Net expected loss to be paid (recovered), end of period | 141 | $ 150 | 101
Period after the end of the reporting period within which the ceded paid losses are typically settled (in days) |  | 45 days |
Public finance |  |  |
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |
Net expected loss to be paid (recovered), beginning of period | 95 | $ 116 | 116
Total economic loss development (benefit) | 47 | 53 |
Net (paid) recovered losses | (11) | (12) |
Net expected loss to be paid (recovered), end of period | 131 | 157 | 95
Other structured finance |  |  |
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |
Net expected loss to be paid (recovered), beginning of period | 60 | 33 | 33
Total economic loss development (benefit) | (1) | (65) |
Net (paid) recovered losses | (1) | 62 |
Net expected loss to be paid (recovered), end of period | 58 | 30 | 60
Structured finance |  |  |
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |
Net expected loss to be paid (recovered), beginning of period | 6 | (10) | (10)
Total economic loss development (benefit) | (3) | (68) |
Net (paid) recovered losses | 7 | 71 |
Net expected loss to be paid (recovered), end of period | $ 10 | (7) | $ 6
Minimum |  |  |
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |
Risk free discount rate | 1.93% |  | 1.93%
Maximum |  |  |
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |
Risk free discount rate | 5.68% |  | 5.35%
Weighted Average |  |  |
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |
Risk free discount rate | 4.16% |  | 3.92%
United States | Public finance |  |  |
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |
Net expected loss to be paid (recovered), beginning of period | $ (31) | 18 | $ 18
Total economic loss development (benefit) | 45 | 29 |
Net (paid) recovered losses | (11) | (12) |
Net expected loss to be paid (recovered), end of period | 3 | 35 | (31)
United States | RMBS |  |  |
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |
Net expected loss to be paid (recovered), beginning of period | (54) | (43) | (43)
Changes in discount rates | 0 | 1 |
Total economic loss development (benefit) | (2) | (3) |
Net (paid) recovered losses | 8 | 9 |
Net expected loss to be paid (recovered), end of period | (48) | (37) | (54)
Non-U.S. public finance | Public finance |  |  |
Present Value of Net Expected Loss and Loss Adjustment Expenses to be Paid [Roll Forward] |  |  |
Net expected loss to be paid (recovered), beginning of period | 126 | 98 | 98
Total economic loss development (benefit) | 2 | 24 |
Net (paid) recovered losses | 0 | 0 |
Net expected loss to be paid (recovered), end of period | $ 128 | $ 122 | $ 126

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