Variable Interest Entities (Narrative) (Detail) $ in Millions	3 Months Ended
	Sep. 30, 2022 USD ($)	Mar. 31, 2022	Sep. 30, 2021 USD ($)	Jun. 30, 2021 USD ($)	Mar. 31, 2021	Dec. 31, 2021 USD ($)
Variable Interest Entity [Line Items]
Carrying amounts of assets	$ 4,015					$ 4,696
Carrying amounts of liabilities	4,864					4,996
Variable Interest Entity Primary Beneficiary [Member]
Variable Interest Entity [Line Items]
Gains (losses) on the consolidation and deconsolidation	0
Variable Interest Entity Primary Beneficiary [Member] | Structured Finance and International Insurance [Member]
Variable Interest Entity [Line Items]
Carrying amounts of assets	153					169
Carrying amounts of liabilities	$ 180					$ 291
Number of variable interest entities consolidated	1		1	2
Number of variable interest entities deconsolidated	1	0			0
Variable Interest Entity Primary Beneficiary [Member] | 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			$ (10)	$ (5)