Operating Segments (Schedule of Segment Reporting Information, by Segment) (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) from discontinued operations including noncontrolling interest	[1]	(3)	65	15	119
Net income (loss) attributable to Dominion Energy		778	654	1,036	1,947
Operating Segments
Segment Reporting Information [Line Items]
Operating Revenue		4,386	3,175	12,261	10,081
Adjustments & Eliminations
Segment Reporting Information [Line Items]
Operating Revenue		0	18	0	46
Net Income (Loss) from discontinued operations including noncontrolling interest		0	0	0	0
Net income (loss) attributable to Dominion Energy		0	0	0	0
Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue		0	1	0	3
Adjustments & Eliminations
Segment Reporting Information [Line Items]
Operating Revenue		(228)	(236)	(699)	(737)
Eliminations
Segment Reporting Information [Line Items]
Operating Revenue		(228)	(218)	(699)	(691)
Dominion Energy Virginia
Segment Reporting Information [Line Items]
Operating Revenue		2,867	2,330	7,208	6,062
Dominion Energy Virginia | Operating Segments
Segment Reporting Information [Line Items]
Operating Revenue		2,871	2,333	7,218	6,072
Net Income (Loss) from discontinued operations including noncontrolling interest		0	0	0	0
Net income (loss) attributable to Dominion Energy		617	599	1,575	1,464
Dominion Energy Virginia | Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue		(4)	(3)	(10)	(10)
Gas Distribution
Segment Reporting Information [Line Items]
Operating Revenue		437	373	2,232	1,804
Gas Distribution | Operating Segments
Segment Reporting Information [Line Items]
Operating Revenue		436	372	2,230	1,800
Net Income (Loss) from discontinued operations including noncontrolling interest		0	0	0	0
Net income (loss) attributable to Dominion Energy		67	69	486	415
Gas Distribution | Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue		1	1	2	4
Dominion Energy South Carolina
Segment Reporting Information [Line Items]
Operating Revenue		917	800	2,531	2,235
Dominion Energy South Carolina | Operating Segments
Segment Reporting Information [Line Items]
Operating Revenue		915	799	2,525	2,230
Net Income (Loss) from discontinued operations including noncontrolling interest		0	0	0	0
Net income (loss) attributable to Dominion Energy		175	151	408	337
Dominion Energy South Carolina | Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue		2	1	6	5
Contracted Assets
Segment Reporting Information [Line Items]
Operating Revenue		244	282	660	845
Contracted Assets | Operating Segments
Segment Reporting Information [Line Items]
Operating Revenue		239	265	645	790
Net Income (Loss) from discontinued operations including noncontrolling interest		0	0	0	0
Net income (loss) attributable to Dominion Energy		121	119	242	373
Contracted Assets | Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue		5	17	15	55
Corporate and Other
Segment Reporting Information [Line Items]
Operating Revenue		149	(391)	329	(171)
Corporate and Other | Operating Segments
Segment Reporting Information [Line Items]
Operating Revenue		(75)	(612)	(357)	(857)
Net Income (Loss) from discontinued operations including noncontrolling interest		(3)	65	15	119
Net income (loss) attributable to Dominion Energy		(202)	(284)	(1,675)	(642)
Corporate and Other | Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue		$ 224	$ 221	$ 686	$ 686

[1] Includes income tax expense (benefit) of $(6) million for the three months ended September 30, 2021 and $4 million and $5 million for the nine months ended September 30, 2022 and 2021, respectively. There were no such amounts recorded during the three months ended September 30, 2022.