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Outstanding Exposure - Schedule of Non-Financial Guaranty Exposure (Details) - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2024
--- | --- | ---
Diversified real estate |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Gross Exposure | $ 2,071 | $ 2,004
Net Exposure | 2,071 | 2,004
Insurance reserve financings and securitizations |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Gross Exposure | 1,502 | 1,449
Net Exposure | 1,179 | 1,126
Pooled corporate obligations |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Gross Exposure | 840 | 868
Net Exposure | 840 | 868
Aircraft residual value insurance |  |
Schedule of Insured Financial Obligations [Line Items] |  |
Gross Exposure | 147 | 147
Net Exposure | $ 87 | $ 87

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