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v3.25.2

Claim and Claim Adjustment Expense Reserves (Net Prior Year Development) (Details) - USD ($) $ in Millions | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2025 | Jun. 30, 2024 | Jun. 30, 2025 | Jun. 30, 2024
Segment Reporting Information [Line Items] |  |  |  |
Pretax (favorable) unfavorable premium development, excluding Life & Group | $ 108 | $ 23 | $ 191 | $ 16
Specialty | Property and Casualty Segments |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Pretax (favorable) unfavorable premium development, excluding Life & Group | 0 | (3) | 10 | (8)
Commercial | Property and Casualty Segments |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Pretax (favorable) unfavorable premium development, excluding Life & Group | (4) | (6) | 47 | (8)
International | Property and Casualty Segments |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Pretax (favorable) unfavorable premium development, excluding Life & Group | 0 | (3) | 0 | (3)
Corporate & Other |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Pretax (favorable) unfavorable premium development, excluding Life & Group | 112 |  | 134 |
Corporate & Other | Property and Casualty Segments |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Pretax (favorable) unfavorable premium development, excluding Life & Group | $ 112 | $ 35 | $ 134 | $ 35

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