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Claim and Claim Adjustment Expense Reserves and Future Policy Benefit 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, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Liability for Claims and Claims Adjustment Expense [Line Items] |  |  |
Net A&EP adverse development before consideration of LPT | $ 92 | $ 143 | $ 125
Provision for uncollectible third-party reinsurance on A&EP | (5) | (5) | (25)
Total additional amounts ceded under LPT | 87 | 138 | 100
Retroactive reinsurance benefit recognized | (91) | (107) | (94)
Pretax impact of deferred retroactive reinsurance | $ (4) | $ 31 | $ 6

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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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