Acquisitions and Dispositions (Schedule of Results of Operations of Disposal Groups Reported As Discontinued Operations) (Detail) - USD ($) $ in Millions		12 Months Ended
		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
Net income (loss) attributable to Dominion Energy		(163)		894		1,358
East Ohio | Enbridge
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Operating revenue		1,037		1,043		908
Operating expense		701	[1]	702	[2]	620
Other income (expense)		30		28		25
Interest and related charges		71		36		18
Income (loss) before income taxes		295		333		295
Income tax expense (benefit)		69	[3]	45		38
Net income (loss) attributable to Dominion Energy		226	[4]	288	[5]	257	[6]
PSNC | Enbridge
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Operating revenue		743		841		613
Operating expense		517	[1]	648	[2]	451
Other income (expense)		11		9		11
Interest and related charges		52		43		35
Income (loss) before income taxes		185		159		138
Income tax expense (benefit)		431	[3]	34		27
Net income (loss) attributable to Dominion Energy		(246)	[4]	125	[5]	111	[6]
Questar Gas and Wexpro | Enbridge
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Operating revenue		1,679		1,341		1,020
Operating expense		1,602	[1]	1,043	[2]	761
Other income (expense)		8				(1)
Interest and related charges		68		45		35
Income (loss) before income taxes		17		253		223
Income tax expense (benefit)		521	[3]	50		42
Net income (loss) attributable to Dominion Energy		(504)	[4]	203	[5]	181	[6]
Other Sales
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Operating revenue		15		11		5
Operating expense		111	[1]	118	[2]	6
Other income (expense)		0
Interest and related charges		1
Income (loss) before income taxes		(97)		(107)		(1)
Income tax expense (benefit)		(38)	[3]	(28)		(1)
Net income (loss) attributable to Dominion Energy		$ (59)	[4]	$ (79)	[5]
Disposition of Gas Transportation & Storage Operations | Q-Pipe Group
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Operating revenue	[7]					254
Operating expense	[7]					76
Other income (expense)	[7],[8]					28
Interest and related charges	[7]					25
Income (loss) before income taxes	[7]					181
Income tax expense (benefit)	[7]					36
Net income (loss) attributable to Dominion Energy	[7],[9]					$ 145

[1] East Ohio Transaction includes a charge of $50 million ($45 million after-tax) primarily for an impairment of associated goodwill, Questar Gas Transaction includes a charge of $284 million ($279 million after-tax) primarily for an impairment of associated goodwill and Other includes a charge of $68 million ($51 million after-tax) associated with the impairment of nonregulated solar generation facility development operations and a charge of $15 million ($11 million after-tax) associated with the impairment of certain nonregulated solar assets.

[2] Other includes a charge of $103 million ($76 million after-tax) associated with the impairment of a nonregulated solar generation asset.

[3] 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.

[4] Excludes $(3) million of income tax expense (benefit) attributable to consolidated state tax adjustments for the year ended December 31, 2023.

[5] Excludes $(3) million of income tax expense (benefit) attributable to consolidated state tax adjustments for the year ended December 31, 2022.

[6] Excludes $19 million of income tax expense (benefit) attributable to consolidated state tax adjustments for the year ended December 31, 2021.

[7] Operations associated with the Q-Pipe Group are through the December 31, 2021 closing date.

[8] Q-Pipe Group includes a $25 million benefit associated with the termination of the Q-Pipe Transaction in 2021.

[9] Excludes $19 million of income tax expense (benefit) attributable to consolidated state and interim period tax allocation adjustments for the year ended December 31, 2021.