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Claim and Claim Adjustment Expense Reserves (International - Net prior year claim and allocated claim adjustment expense reserve development) (Details) - International - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2021 | Sep. 30, 2020 | Sep. 30, 2021 | Sep. 30, 2020
Liability for Claims and Claims Adjustment Expense [Line Items] |  |  |  |
Casualty | $ (4) | $ (5) | $ (3) | $ (11)
Property, Energy and Marine | (14) | 9 | (17) | 10
Specialty | 21 | (4) | 22 | (2)
Total pretax (favorable) unfavorable development | $ 3 | $ 0 | $ 2 | $ (3)

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- Definition Net Prior Year Claim and Allocated Claim Adjustment Expense Reserve Development, Casualty + References No definition available. + Details
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- Definition Net Prior Year Claim And Allocated Claim Adjustment Expense Reserve Development Specialty + References No definition available. + Details
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- Definition Net Prior Year Claim And Allocated Claim Adjustment Expense Reserve Property, Energy and Marine + References No definition available. + Details
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- Definition Pretax (favorable) unfavorable net prior year claim and allocated claim adjustment expense reserve development, excluding Life & Group + References No definition available. + Details
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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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