Acquisitions and Dispositions (Business Review Dispositions) (Narrative) (Detail) - USD ($) $ in Millions		1 Months Ended	3 Months Ended	12 Months Ended
		Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021	Feb. 23, 2024	Sep. 30, 2023	Aug. 31, 2023
Business Acquisition And Dispositions [Line Items]
State				$ 282	$ 73	$ (49)
Goodwill write-off	[1]				110
Deferred taxes				1,471	$ 102	$ 409
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
Termination fee								155
Goodwill write-off		$ 1,500
Deferred taxes				$ 29
Disposal group, transition services description				At the closing of the East Ohio 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 East Ohio for up to approximately two years. Enbridge has also agreed to provide certain services to Dominion Energy.
Impairment of goodwill		50		$ 50
Goodwill impairement after tax		45		45
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
Disposal group, recognized a pre-tax gain (loss)		30
Disposal group, gain (loss) recorded after tax		(370)
Goodwill write-off		700
Deferred taxes				$ 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
Termination fee								$ 107
Goodwill write-off		700		$ 462
Disposal group, transition services description				At the closing of the Questar Gas 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 Questar Gas and Wexpro for up to approximately two years. Enbridge has also agreed to provide certain services to Dominion Energy.
Impairment of goodwill		284		$ 284
Goodwill impairement after tax		$ 279		$ 279
Other Sales | Tredegar Solar Fund I, LLC
Business Acquisition And Dispositions [Line Items]
Disposal group, cash consideration									$ 21
Other Sales | Birdseye
Business Acquisition And Dispositions [Line Items]
Realizable fair value charge			$ 68
Other Sales | Birdseye and Madison
Business Acquisition And Dispositions [Line Items]
Realizable fair value charge net of tax			$ 51
Other Sales | Birdseye and Madison | Subsequent Event
Business Acquisition And Dispositions [Line Items]
Disposal group, cash consideration							$ 17

[1] See Note 3 for additional information.