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Variable Interest Entities (Narrative) (Detail) - Variable Interest Entity, Primary Beneficiary [Member] - Structured Finance and International Insurance [Member] $ in Millions | 3 Months Ended
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Mar. 31, 2024 VariableInterestEntities | Mar. 31, 2023 USD ($) VariableInterestEntities
Variable Interest Entity [Line Items] |  |
Number of variable interest entities deconsolidated | 0 | 1
Number of variable interest entities consolidated | 0 | 0
Recorded Due To Credit Losses in AOCI [Member] |  |
Variable Interest Entity [Line Items] |  |
Net realized gains (losses) related to deconsolidation | $ |  | $ 15

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