Acquisitions and Dispositions (Schedule of Results of Operations of Disposal Groups Reported As Discontinued Operations) (Parenthetical) (Detail) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2023		Dec. 31, 2022	Dec. 31, 2021
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income tax expense (benefit)		$ 1,300		$ 197	$ 374
Benefit associated with the termination					25
Impairment of assets and other charges		307		1,401	194
East Ohio | Enbridge
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Impairment of goodwill	$ 50	50
Goodwill impairement after tax	45	45
Income tax expense (benefit)		69	[1]	45	38
Questar Gas and Wexpro | Enbridge
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Impairment of goodwill	284	284
Goodwill impairement after tax	$ 279	279
Income tax expense (benefit)		521	[1]	50	42
Other
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income tax expense (benefit)		(38)	[1]	(28)	(1)
Other | Nonregulated Solar Assets
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Impairment of assets and other charges		68
Impairment of assets and other charges after tax		51
Other | Nonregulated Solar Generation Facility
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Impairment of assets and other charges		15		103
Impairment of assets and other charges after tax		11		76
East Ohio, PSNC and Questar Gas
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income tax expense (benefit)		$ (3)		$ (3)	19
Gas, Transmission & Storage
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income tax expense (benefit)					$ 19

[1] Includes amounts to reflect the recognition of deferred taxes on the outside basis of the applicable entities’ stock upon meeting the classification as held for sale.