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Claim, Claim Adjustment Expense 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, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Liability for Claims and Claims Adjustment Expense [Line Items] |  |  |
Net A&EP adverse development before consideration of LPT | $ 143 | $ 125 | $ 150
Provision for uncollectible third-party reinsurance on A&EP | (5) | (25) | (25)
Total additional amounts ceded under LPT | 138 | 100 | 125
Retroactive reinsurance benefit recognized | (107) | (94) | (107)
Pretax impact of deferred retroactive reinsurance | $ 31 | $ 6 | $ 18

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- Details
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