Operating Segments (Schedule of Segment Reporting Information, by Segment) (Detail) - USD ($) $ in Millions		3 Months Ended
		Mar. 31, 2025		Mar. 31, 2024	Dec. 31, 2024	[6]
Segment Reporting Information [Line Items]
Operating Revenue		$ 4,076		$ 3,632
Electric fuel and other energy-related purchases	[1]	962		959
Purchased electric capacity	[1]	9		12
Purchased gas	[1]	147		120
Other operations and maintenance	[1],[2]	944		885
Depreciation and amortization	[1]	582		621
Other taxes	[1]	209		202
Total operating expenses		2,853		2,799
Interest and related charges	[1]	480		574
Income tax expense (benefit)	[1]	55		55
Equity in earnings (losses) of equity method investees	[3]	(7)
Other income (expense)	[3]	(23)		66
Interest income	[3]	35		53
Net Income (Loss) From Discontinued Operations Including Noncontrolling Interests	[4]	(1)		118
Noncontrolling Interests		46		0
Net income (loss) attributable to Dominion Energy		646		441
Investment in equity method investees		132	[5]		$ 138
Capital expenditures		3,214		2,930
Total assets		104,555			$ 102,415
Operating Segments
Segment Reporting Information [Line Items]
Total revenue from external customers		4,076		3,632
Adjustments & Eliminations
Segment Reporting Information [Line Items]
Operating Revenue		(314)		(237)
Electric fuel and other energy-related purchases	[1]	(3)		(1)
Purchased electric capacity	[1]	0		0
Purchased gas	[1]	0		0
Other operations and maintenance	[1],[2]	(308)		(234)
Depreciation and amortization	[1]	0		0
Other taxes	[1]	(3)		(2)
Total operating expenses		(314)		(237)
Interest and related charges	[1]	(49)		(36)
Income tax expense (benefit)	[1]	0		0
Equity in earnings (losses) of equity method investees	[3]	0
Other income (expense)	[3]	0		0
Interest income	[3]	(49)		(36)
Net Income (Loss) From Discontinued Operations Including Noncontrolling Interests		0		0
Noncontrolling Interests		0
Net income (loss) attributable to Dominion Energy		0		0
Investment in equity method investees	[5]	0
Capital expenditures		0		0
Total assets		(6,000)
Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue		0		0
Adjustments & Eliminations
Segment Reporting Information [Line Items]
Operating Revenue		(314)		(237)
Eliminations
Segment Reporting Information [Line Items]
Total revenue from external customers		0		0
Dominion Energy Virginia | Operating Segments
Segment Reporting Information [Line Items]
Total revenue from external customers		2,795		2,489
Operating Revenue		2,794		2,489
Electric fuel and other energy-related purchases	[1]	769		701
Purchased electric capacity	[1]	7		13
Purchased gas	[1]	0		0
Other operations and maintenance	[1],[2]	559		533
Depreciation and amortization	[1]	397		445
Other taxes	[1]	97		93
Total operating expenses		1,829		1,785
Interest and related charges	[1]	245		192
Income tax expense (benefit)	[1]	132		116
Equity in earnings (losses) of equity method investees	[3]	0
Other income (expense)	[3]	35		21
Interest income	[3]	6		7
Net Income (Loss) From Discontinued Operations Including Noncontrolling Interests		0		0
Noncontrolling Interests		68
Net income (loss) attributable to Dominion Energy		561		424
Investment in equity method investees	[5]	0
Capital expenditures		2,724		2,102
Total assets		71,900
Dominion Energy Virginia | Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue		(1)		0
Dominion Energy South Carolina | Operating Segments
Segment Reporting Information [Line Items]
Total revenue from external customers		949		892
Operating Revenue		951		893
Electric fuel and other energy-related purchases	[1]	167		233
Purchased electric capacity	[1]	2		(1)
Purchased gas	[1]	147		120
Other operations and maintenance	[1],[2]	178		166
Depreciation and amortization	[1]	141		136
Other taxes	[1]	79		75
Total operating expenses		714		729
Interest and related charges	[1]	71		67
Income tax expense (benefit)	[1]	18		18
Equity in earnings (losses) of equity method investees	[3]	0
Other income (expense)	[3]	(0)		(1)
Interest income	[3]	4		2
Net Income (Loss) From Discontinued Operations Including Noncontrolling Interests		0		0
Noncontrolling Interests		0
Net income (loss) attributable to Dominion Energy		152		80
Investment in equity method investees	[5]	0
Capital expenditures		297		268
Total assets		18,500
Dominion Energy South Carolina | Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue		2		1
Contracted Energy | Operating Segments
Segment Reporting Information [Line Items]
Total revenue from external customers		304		306
Operating Revenue		307		308
Electric fuel and other energy-related purchases	[1]	29		26
Purchased electric capacity	[1]	0		0
Purchased gas	[1]	0		0
Other operations and maintenance	[1],[2]	111		104
Depreciation and amortization	[1]	22		18
Other taxes	[1]	15		14
Total operating expenses		177		162
Interest and related charges	[1]	8		9
Income tax expense (benefit)	[1]	35		38
Equity in earnings (losses) of equity method investees	[3]	0
Other income (expense)	[3]	(7)		(21)
Interest income	[3]	29		44
Net Income (Loss) From Discontinued Operations Including Noncontrolling Interests		0		0
Noncontrolling Interests		0
Net income (loss) attributable to Dominion Energy		109		122
Investment in equity method investees	[5]	91
Capital expenditures		179		313
Total assets		9,800
Contracted Energy | Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue		3		2
Corporate and Other | Operating Segments
Segment Reporting Information [Line Items]
Total revenue from external customers		28		(55)
Operating Revenue		338		179
Electric fuel and other energy-related purchases	[1]	0		0
Purchased electric capacity	[1]	0		0
Purchased gas	[1]	0		0
Other operations and maintenance	[1],[2]	404		316
Depreciation and amortization	[1]	22		22
Other taxes	[1]	21		22
Total operating expenses		447		360
Interest and related charges	[1]	205		342
Income tax expense (benefit)	[1]	(130)		(117)
Equity in earnings (losses) of equity method investees	[3]	(7)
Other income (expense)	[3]	(51)		67
Interest income	[3]	45		36
Net Income (Loss) From Discontinued Operations Including Noncontrolling Interests		(1)		118
Noncontrolling Interests		(22)
Net income (loss) attributable to Dominion Energy		(176)		(185)
Investment in equity method investees	[5]	41
Capital expenditures		14		247
Total assets		10,400
Corporate and Other | Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue		$ 310		$ 234

[1] The significant expense categories and amounts in the segment information presented above align with the segment-level information that is regularly provided to Dominion Energy’s CODM.

[2] Includes impairment of assets and other charges (benefits).

[3] Items designated are other segment items for each reportable segment.

[4] Includes income tax expense of less than $1 million and $54 million for the three months ended March 31, 2025 and 2024, respectively.

[5] Excludes liability to Atlantic Coast Pipeline.

[6] Dominion Energy’s Consolidated Balance Sheet at December 31, 2024 has been derived from the audited Consolidated Balance Sheet at that date.