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v3.25.3

Outstanding Exposure - Additional Information (Details) $ in Millions | 9 Months Ended |  |
--- | --- | --- | ---
Sep. 30, 2025 USD ($) Category | Dec. 31, 2024 USD ($) | Dec. 31, 2023 USD ($)
Schedule of Insured Financial Obligations [Line Items] |  |  |
Number of surveillance categories | Category | 3 |  |
Loss mitigation securities | $ 801 | $ 1,200 |
Aircraft residual value insurance (RVI) |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |
Residual value insurance policies exposure downgraded | 147 | 147 |
Net Exposure | 87 | 87 |
Specialty business, contingent, gross par | 60 |  |
Aircraft residual value insurance (RVI) | BIG |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |
Residual value insurance policies exposure downgraded | 5 | 5 |
Net Exposure | 5 | $ 5 |
Commitment to Provide Guarantees | Public finance |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |
Outstanding commitments to provide guaranties | 1,600 |  |
Potential future commitment |  |  | $ 353
Commitment to Provide Guarantees | Structured finance |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |
Outstanding commitments to provide guaranties | $ 2,200 |  |
Potential future commitment |  |  | $ 50
Minimum |  |  |
Schedule of Insured Financial Obligations [Line Items] |  |  |
Probability of paying more claims than being reimbursed (as a percent) | 50.00% |  |

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