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Claim and Claim Adjustment Expense Reserves and Future Policy Benefit Reserves (Net prior year development) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021
Segment Reporting Information [Line Items] |  |  |  |
Pretax (favorable) unfavorable premium development, excluding Life & Group | $ (17) | $ (10) | $ (2) | $ 4
Specialty |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Pretax (favorable) unfavorable premium development, excluding Life & Group | (15) | (15) | (35) | (40)
Commercial |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Pretax (favorable) unfavorable premium development, excluding Life & Group | (2) | 2 | (26) | 2
International |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Pretax (favorable) unfavorable premium development, excluding Life & Group | 0 | 3 | (5) | 2
Corporate & Other |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Pretax (favorable) unfavorable premium development, excluding Life & Group | $ 0 | $ 0 | $ 64 | $ 40

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- Definition Pretax Favorable Unfavorable Premium Development, excluding Life & Group + References No definition available. + Details
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- Details
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