Operating Segments (Schedule of Segment Reporting Information, by Segment, Virginia Power) (Detail) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Segment Reporting Information [Line Items]
Operating Revenue		$ 4,386	$ 3,176	$ 12,261	$ 10,084
Net income (loss) attributable to Dominion Energy		778	654	1,036	1,947
Virginia Electric and Power Company
Segment Reporting Information [Line Items]
Operating Revenue	[1]	2,875	1,976	7,217	5,547
Net income (loss) attributable to Dominion Energy		571	556	975	1,344
Dominion Energy Virginia
Segment Reporting Information [Line Items]
Operating Revenue		2,867	2,330	7,208	6,062
Dominion Energy Virginia | Virginia Electric and Power Company
Segment Reporting Information [Line Items]
Operating Revenue		2,865	2,326	7,200	6,048
Net income (loss) attributable to Dominion Energy		618	601	1,576	1,462
Corporate and Other
Segment Reporting Information [Line Items]
Operating Revenue		149	(391)	329	(171)
Corporate and Other | Virginia Electric and Power Company
Segment Reporting Information [Line Items]
Operating Revenue		10	(350)	17	(501)
Net income (loss) attributable to Dominion Energy		$ (47)	$ (45)	$ (601)	$ (118)

[1] See Note 19 for amounts attributable to affiliates.