Variable Interest Entities (Narrative) (Detail) - Variable Interest Entity, Primary Beneficiary [Member] - Structured Finance and International Insurance [Member] $ in Millions	3 Months Ended
	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