Acquisitions and Dispositions (Business Review Dispositions) (Narrative) (Detail) - USD ($) $ in Millions	3 Months Ended				6 Months Ended		12 Months Ended
	Jun. 30, 2024	Mar. 31, 2024	Dec. 31, 2023	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2023	Feb. 29, 2024	Sep. 30, 2023
Business Acquisition And Dispositions [Line Items]
Income tax expense (benefit)	$ 95			$ 98	$ 229	$ 274
Deferred income tax expense (benefit)					(54)	$ 340
East Ohio | Enbridge
Business Acquisition And Dispositions [Line Items]
Disposal group, total value of consideration									$ 6,600
Disposal group, cash consideration									4,300
Disposal group, indebtedness									2,300
Disposal group, recognized a pre-tax gain (loss)					102
Disposal group, gain (loss) recorded after tax					113
Goodwill write-off					$ 1,500
Deferred income tax expense (benefit)							$ 29
Disposal group, transition services description					At the closing of the East Ohio Transaction, Dominion Energy and Enbridge entered into a transition services agreement pursuant to which Dominion Energy will continue to provide certain services to support the ongoing operations of East Ohio for up to approximately two years. Enbridge has also agreed to provide certain services to Dominion Energy.
PSNC | Enbridge
Business Acquisition And Dispositions [Line Items]
Disposal group, total value of consideration									3,100
Disposal group, cash consideration									2,200
Disposal group, indebtedness									1,000
Termination fee	$ 78				$ 78
Disposal group, recognized a pre-tax gain (loss)					70
Disposal group, gain (loss) recorded after tax					50
Goodwill write-off					700
Deferred tax of classified held for sale					$ 16		334
Disposal group, transition services description					At the closing of the PSNC Transaction, Dominion Energy and Enbridge will enter into a transition services agreement pursuant to which Dominion Energy will continue to provide certain services to support the ongoing operations of PSNC for up to approximately two years. Enbridge has also agreed to provide certain services to Dominion Energy.
Questar Gas and Wexpro | Enbridge
Business Acquisition And Dispositions [Line Items]
Disposal group, total value of consideration									4,300
Disposal group, cash consideration									3,000
Disposal group, indebtedness									$ 1,300
Disposal group, recognized a pre-tax gain (loss)		$ 78			$ 31		284
Disposal group, gain (loss) recorded after tax		78			17		279
Goodwill write-off					$ 700
Income tax expense (benefit)		(5)
Deferred income tax expense (benefit)		$ 22					$ 462
Disposal group, transition services description					At the closing of the Questar Gas Transaction, Dominion Energy and Enbridge entered into a transition services agreement pursuant to which Dominion Energy will continue to provide certain services to support the ongoing operations of Questar Gas and Wexpro for up to approximately two years. Enbridge has also agreed to provide certain services to Dominion Energy.
Other Sales | Tredegar Solar Fund I, LLC
Business Acquisition And Dispositions [Line Items]
Realizable fair value charge net of tax			$ 68
Realizable fair value charge net of tax			$ 51
Other Sales | Birdseye and Madison [Member]
Business Acquisition And Dispositions [Line Items]
Disposal group, cash consideration								$ 17