Variable Interest Entities (Detail) - USD ($) $ in Millions	Sep. 30, 2025	Dec. 31, 2024
Variable Interest Entity
Carrying value of debt	$ 23,362	$ 23,900
Assets	45,608	44,567
Variable Interest Entity, Primary Beneficiary [Member]
Variable Interest Entity
Assets	138	128
Low income housing investments [Member] | Variable Interest Entity, Not Primary Beneficiary [Member]
Variable Interest Entity
Aggregate investment balance	636	707
Carrying value of debt	635	670
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	$ 121	$ 111