Variable Interest Entities (Detail) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Variable Interest Entity
Aggregate investment balance	$ 538	$ 460
Carrying value of debt	16,229	14,984
Assets	32,823	31,367
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity
Assets	119	113
Low income housing investments [Member] | Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity
Aggregate investment balance	458	321
Carrying value of debt	408	295
Trust For Final Capping, Closure, Post-closure Or Environmental Remediation Obligations [Member] | Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity
Aggregate investment balance	$ 104	$ 93