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Variable Interest Entities (Narrative) (Detail) - Variable Interest Entity, Primary Beneficiary [Member] $ in Millions	3 Months Ended
	Sep. 30, 2025 VariableInterestEntities	Jun. 30, 2025 VariableInterestEntities	Mar. 31, 2025 VariableInterestEntities	Sep. 30, 2024 VariableInterestEntities	Jun. 30, 2024 USD ($) VariableInterestEntities	Mar. 31, 2024 VariableInterestEntities
Recorded Due To Credit Losses in AOCI [Member]
Variable Interest Entity [Line Items]
Net realized gains (losses) related to deconsolidation | $					$ (9)
Structured Finance and International Insurance [Member]
Variable Interest Entity [Line Items]
Number of variable interest entities deconsolidated	0	0	0	0	1	0
Net realized gains (losses) related to deconsolidation | $					$ (14)
Number of variable interest entities consolidated		0	0	0	0	0
Structured Finance and International Insurance [Member] | Insured RMBS Security [Member]
Variable Interest Entity [Line Items]
Number of variable interest entities consolidated	1

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Number of variable interest entities consolidated.

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Amount of gain (loss) from deconsolidation of subsidiary and derecognition of group of assets constituting transfer of business or nonprofit activity, excluding conveyance of oil and gas mineral rights and transfer of good or service in contract with customer.

+ References

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