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Claim and Claim Adjustment Expense Reserves and Future Policy Benefit Reserves (Specialty - Net prior year claim and allocated claim adjustment expense reserve development) (Details) - Specialty - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2022 | Sep. 30, 2021 | Sep. 30, 2022 | Sep. 30, 2021
Liability for Claims and Claims Adjustment Expense [Line Items] |  |  |  |
Medical Professional Liability | $ 8 | $ 8 | $ 17 | $ 16
Other Professional Liability and Management Liability | 9 | 0 | 22 | 10
Surety | (20) | (15) | (48) | (53)
Warranty | (13) | (6) | (22) | (14)
Other | 1 | (2) | (4) | 1
Total pretax (favorable) unfavorable development | $ (15) | $ (15) | $ (35) | $ (40)

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- Definition Net prior year claim and allocated claim adjustment expense reserve development, Medical Professional Liability + References No definition available. + Details
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- Definition Net prior year claim and allocated claim adjustment expense reserve development, Other + References No definition available. + Details
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- Definition Net Prior Year Claim And Allocated Claim Adjustment Expense Reserve Development, Other Professional Liability And Management Liability + References No definition available. + Details
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- Definition Net prior year claim and allocated claim adjustment expense reserve development, Surety + References No definition available. + Details
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- Definition Net prior year claim and allocated claim adjustment expense reserve development, Warranty + 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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