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Commitments, Guarantees and Contingent Liabilities - California Earthquake Authority (Narrative) (Details) - California Earthquake Authority - USD ($) $ in Millions | Sep. 30, 2025 | Dec. 31, 2025
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Loss Contingencies |  |
CEA capital balance | $ 6,300 |
Proceeds of revenue bonds | 2,700 |
CEA existing reinsurance layer | 7,700 |
Policy holder surcharge | 1,000 |
Current estimated maximum CEA assessment | 1,700 |
CEA capital balance threshold | 350 |
CEA capital balance to be restored | 350 |
Projected aggregate claim paying capacity | $ 19,300 |
Share of the CEA (as a percent) |  | 7.90%
Maximum possible assessment |  | $ 131

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