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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
	Dec. 31, 2024 VariableInterestEntities	Sep. 30, 2024 VariableInterestEntities	Jun. 30, 2024 USD ($) VariableInterestEntities	Mar. 31, 2024 VariableInterestEntities	Dec. 31, 2023 VariableInterestEntities	Sep. 30, 2023 USD ($) VariableInterestEntities	Jun. 30, 2023 USD ($) VariableInterestEntities	Mar. 31, 2023 USD ($) VariableInterestEntities
Variable Interest Entity [Line Items]
Number of variable interest entities deconsolidated | VariableInterestEntities	0	0	0	0	0	1	1	1
Net realized gains (losses) related to deconsolidation | $			$ (14)
Number of variable interest entities consolidated | VariableInterestEntities					0
Recorded Due To Credit Losses in AOCI [Member]
Variable Interest Entity [Line Items]
Net realized gains (losses) related to deconsolidation | $			$ (9)			$ (7)	$ (7)	$ (15)

X

- Definition

Number of variable interest entities consolidated.

+ References

No definition available.

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- Definition

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+ References

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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

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 810
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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