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v3.21.2

Claim and Claim Adjustment Expense Reserves (Net prior year development) (Details) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Segment Reporting Information [Line Items] |  |  |  |
Pretax (favorable) unfavorable premium development, excluding Life & Group | $ (10) | $ (15) | $ 4 | $ (8)
Specialty |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Pretax (favorable) unfavorable premium development, excluding Life & Group | (15) | (16) | (40) | (47)
Commercial |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Pretax (favorable) unfavorable premium development, excluding Life & Group | 2 | 1 | 2 | (8)
International |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Pretax (favorable) unfavorable premium development, excluding Life & Group | 3 | 0 | 2 | (3)
Corporate & Other |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |
Pretax (favorable) unfavorable premium development, excluding Life & Group | $ 0 | $ 0 | $ 40 | $ 50

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Details
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- Details
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- Details
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