Acquisitions and Dispositions (Schedule of Results of Operations of Disposal Groups Reported As Discontinued Operations) (Detail) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2024		Dec. 31, 2023		Dec. 31, 2022
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Income tax expense (benefit)		$ 31		$ 1,300		$ 207
Net income (loss) attributable to Dominion Energy		197		(125)		922	[1]
Tredegar Solar Fund I, LLC
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Operating revenue				15
Operating expense	[2]			111
Other income (expense)				0
Interest and related charges				1
Income (loss) before income taxes				(97)
Income tax expense (benefit)	[3]			(38)
Net income (loss) attributable to Dominion Energy	[4]			(59)
East Ohio | Enbridge
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Operating revenue		229	[5]	1,037		1,043
Operating expense		247	[5],[6]	701	[2]	702	[7]
Other income (expense)		(17)	[5]	30		28
Interest and related charges		15	[5]	71		36
Income (loss) before income taxes		(50)	[5]	295		333
Income tax expense (benefit)		11	[5]	69	[3]	45
Net income (loss) attributable to Dominion Energy		(61)	[5],[8]	226	[4]	288	[9]
PSNC | Enbridge
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Operating revenue		488	[5]	743		841
Operating expense		313	[5],[6]	517	[2]	648	[7]
Other income (expense)		11	[5]	11		9
Interest and related charges		44	[5]	52		43
Income (loss) before income taxes		142	[5]	185		159
Income tax expense (benefit)		44	[5]	431	[3]	34
Net income (loss) attributable to Dominion Energy		98	[5],[8]	(246)	[4]	125	[9]
Questar Gas and Wexpro | Enbridge
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Operating revenue		894	[5]	1,679		1,341
Operating expense		724	[5],[6]	1,554	[2]	1,043	[7]
Other income (expense)		2	[5]	8		37
Interest and related charges		25	[5]	68		45
Income (loss) before income taxes		147	[5]	65		290
Income tax expense (benefit)		54	[5]	531	[3]	60
Net income (loss) attributable to Dominion Energy		93	[5],[8]	$ (466)	[4]	230	[9]
Other Sales
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Operating expense	[6]	(8)
Income (loss) before income taxes		8
Net income (loss) attributable to Dominion Energy	[8]	$ 8
Other Sales | Tredegar Solar Fund I, LLC
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Operating revenue						11
Operating expense	[7]					118
Income (loss) before income taxes						(107)
Income tax expense (benefit)						(28)
Net income (loss) attributable to Dominion Energy	[9]					$ (79)

[1] As discussed in Note 19, effective in June 2022 through its redemption in September 2022, the Series A Preferred Stock was considered to be mandatorily redeemable and was classified in current liabilities.

[2] 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 $236 million ($231 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.

[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] Represents amounts attributable to Dominion Energy prior to the closing of the East Ohio Transaction which closed on March 6, 2024, the PSNC Transaction which closed on September 30, 2024 and the Questar Gas Transaction which closed on May 31, 2024.

[6] East Ohio Transaction includes a charge of $45 million ($33 million after-tax) associated with an increase to certain pension retirement benefits attributable to a plan amendment and a contribution to the defined contribution employee savings plan. See Note 22 for further information on these transactions.

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

[8] Excludes $(69) million of income tax expense (benefit) attributable to consolidated state tax adjustments for the year ended December 31, 2024.

[9] Excludes $(4) million of income tax expense (benefit) attributable to consolidated state tax adjustments for the year ended December 31, 2022.