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Variable Interest Entities (Narrative) (Detail) - Variable Interest Entity, Primary Beneficiary [Member] $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2023 USD ($) VariableInterestEntities | Jun. 30, 2023 USD ($) VariableInterestEntities | Mar. 31, 2023 USD ($) VariableInterestEntities | Sep. 30, 2022 USD ($) VariableInterestEntities | Jun. 30, 2022 VariableInterestEntities | Mar. 31, 2022 VariableInterestEntities | Sep. 30, 2023 VariableInterestEntities
Variable Interest Entity [Line Items] |  |  |  |  |  |  |
Gains (losses) on the consolidation and deconsolidation | $ |  |  |  | $ 0 |  |  |
Structured Finance and International Insurance [Member] |  |  |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |  |  |
Number of variable interest entities deconsolidated | VariableInterestEntities | 1 | 1 | 1 | 1 | 0 | 0 |
Number of variable interest entities consolidated | VariableInterestEntities |  |  |  | 1 |  |  | 0
Structured Finance and International Insurance [Member] | Recorded Due To Credit Losses in AOCI [Member] |  |  |  |  |  |  |
Variable Interest Entity [Line Items] |  |  |  |  |  |  |
Net realized gains (losses) related to deconsolidation | $ | $ (7) | $ (7) | $ (15) |  |  |  |

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- Definition Gains losses on the consolidation and deconsolidation. + References No definition available. + Details
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- Definition The gain (loss) recognized on initial consolidation of a variable interest entity (VIE) when the VIE is not a business (as defined). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Name Accounting Standards Codification -Topic 810 -SubTopic 10 -Section 50 -Paragraph 3 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481203/810-10-50-3 + Details
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