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v3.25.1

Property Casualty Loss and Loss Expenses - Narrative (Details) - USD ($) $ in Millions | 3 Months Ended |
--- | --- | ---
Mar. 31, 2025 | Mar. 31, 2024 | Dec. 31, 2024
SEC Schedule, 12-18, Supplemental Information, Property-Casualty Insurance Underwriters |  |  |
Reserve for loss and loss expenses | $ 10,780 |  | $ 10,003
Prior accident years | (91) | $ (100) |
Life Insurance Segment |  |  |
SEC Schedule, 12-18, Supplemental Information, Property-Casualty Insurance Underwriters |  |  |
Reserve for loss and loss expenses | 73 | 68 |
Commercial Insurance |  |  |
SEC Schedule, 12-18, Supplemental Information, Property-Casualty Insurance Underwriters |  |  |
Prior accident years | (43) | (38) |
Commercial Insurance | Commercial Property Line |  |  |
SEC Schedule, 12-18, Supplemental Information, Property-Casualty Insurance Underwriters |  |  |
Prior accident years | (35) | (22) |
Commercial Insurance | Workers' Compensation Line |  |  |
SEC Schedule, 12-18, Supplemental Information, Property-Casualty Insurance Underwriters |  |  |
Prior accident years | (11) | (12) |
Personal Insurance |  |  |
SEC Schedule, 12-18, Supplemental Information, Property-Casualty Insurance Underwriters |  |  |
Prior accident years | (19) | (33) |
Personal Insurance | Personal Auto |  |  |
SEC Schedule, 12-18, Supplemental Information, Property-Casualty Insurance Underwriters |  |  |
Prior accident years |  | (5) |
Personal Insurance | Homeowner |  |  |
SEC Schedule, 12-18, Supplemental Information, Property-Casualty Insurance Underwriters |  |  |
Prior accident years | (19) | (25) |
Excess and Surplus Lines Insurance |  |  |
SEC Schedule, 12-18, Supplemental Information, Property-Casualty Insurance Underwriters |  |  |
Prior accident years | $ (9) | $ (3) |

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