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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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Jun. 30, 2023 USD ($) | Mar. 31, 2023 USD ($) | Jun. 30, 2022 | Mar. 31, 2022
Variable Interest Entity [Line Items] |  |  |  |
Number of variable interest entities deconsolidated | 1 | 1 | 0 | 0
Recorded Due To Credit Losses in AOCI [Member] |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |
Net realized gains (losses) related to deconsolidation | $ (7) | $ (15) |  |

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