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Claim and Claim Adjustment Expense Reserves (Impact of Loss Portfolio Transfer on the Consolidated Statement of Operations) (Details) - Asbestos and Environmental Reserves - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2024 | Dec. 31, 2023 | Dec. 31, 2022
Liability for Claims and Claims Adjustment Expense [Line Items] |  |  |
Net A&EP adverse development before consideration of LPT | $ 103 | $ 86 | $ 92
Provision for uncollectible third-party reinsurance on A&EP | 0 | 0 | (5)
Total additional amounts ceded under LPT | 103 | 86 | 87
Retroactive reinsurance benefit recognized | (95) | (94) | (91)
Pretax impact of deferred retroactive reinsurance | $ 8 | $ (8) | $ (4)

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- Definition Net AEP adverse development before consideration of LPT + References No definition available. + Details
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- Definition Policyholder Benefits and Claims Incurred, Additional Amount Ceded + References No definition available. + Details
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- Definition Provision For Uncollectible Third-Party Reinsurance + 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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