Operating Segments (Schedule of Segment Reporting Information, by Segment) (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2024	Mar. 31, 2023
Segment Reporting Information [Line Items]
Operating Revenue		$ 3,632	$ 3,883
Net Income from discontinued operations including noncontrolling interest	[1]	114	281
Net income attributable to Dominion Energy		674	981
Operating Segments
Segment Reporting Information [Line Items]
Total revenue from external customers		3,632	3,883
Adjustments & Eliminations
Segment Reporting Information [Line Items]
Total revenue from external customers		0	0
Net Income from discontinued operations including noncontrolling interest		0	0
Net income attributable to Dominion Energy		0	0
Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue		0	0
Adjustments & Eliminations
Segment Reporting Information [Line Items]
Operating Revenue		(237)	(236)
Eliminations
Segment Reporting Information [Line Items]
Operating Revenue		(237)	(236)
Dominion Energy Virginia | Operating Segments
Segment Reporting Information [Line Items]
Total revenue from external customers		2,489	2,384
Operating Revenue		2,489	2,384
Net Income from discontinued operations including noncontrolling interest		0	0
Net income attributable to Dominion Energy		424	386
Dominion Energy Virginia | Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue		0	0
Dominion Energy South Carolina | Operating Segments
Segment Reporting Information [Line Items]
Total revenue from external customers		892	844
Operating Revenue		893	845
Net Income from discontinued operations including noncontrolling interest		0	0
Net income attributable to Dominion Energy		80	91
Dominion Energy South Carolina | Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue		1	1
Contracted Energy | Operating Segments
Segment Reporting Information [Line Items]
Total revenue from external customers		306	308
Operating Revenue		308	311
Net Income from discontinued operations including noncontrolling interest		0	0
Net income attributable to Dominion Energy		122	111
Contracted Energy | Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue		2	3
Corporate and Other | Operating Segments
Segment Reporting Information [Line Items]
Total revenue from external customers		(55)	347
Operating Revenue		179	579
Net Income from discontinued operations including noncontrolling interest		114	281
Net income attributable to Dominion Energy		48	393
Corporate and Other | Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue		$ 234	$ 232

[1] Includes income tax expense of $51 million and $56 million for the three months ended March 31, 2024 and 2023, respectively.