Operating Segments (Schedule of Segment Reporting Information, by Segment) (Detail) - USD ($) $ in Millions		1 Months Ended	3 Months Ended								12 Months Ended
		Dec. 31, 2021	Dec. 31, 2023	Sep. 30, 2023	Jun. 30, 2023	Mar. 31, 2023	Dec. 31, 2022	Sep. 30, 2022	Jun. 30, 2022	Mar. 31, 2022	Dec. 31, 2023		Dec. 31, 2022		Dec. 31, 2021
Segment Reporting Information [Line Items]
Operating Revenue			$ 3,534	$ 3,810	$ 3,166	$ 3,883	$ 3,807	$ 3,961	$ 3,058	$ 3,112	$ 14,393		$ 13,938		$ 11,419
Depreciation and amortization											2,580		2,442		2,117
Equity in earnings of equity method investees											(26)		21		15
Interest income (expense)											107		109		95
Interest and related charges (benefit)											1,674		1,002		1,255
Income tax expense (benefit)		$ 173									575		113		(181)
Net Income (Loss) From Discontinued Operations Including Noncontrolling Interest			(71)	(541)	168	281	122	150	212	410	(163)	[1],[2]	894	[1],[2]	1,358	[1],[2]
Net income (loss) attributable to Dominion Energy			273	$ 157	$ 583	$ 981	344	$ 735	$ (447)	$ 689	1,994		1,321		3,399
Investment in equity method affiliates	[3]		268				295				268		295
Capital expenditures											10,235		7,758		6,061
Total assets			109,032				104,795				109,032		104,795
Operating Segments
Segment Reporting Information [Line Items]
Total revenue from external customers											14,393		13,938		11,419
Net Income (Loss) From Discontinued Operations Including Noncontrolling Interest													894
Adjustments & Eliminations
Segment Reporting Information [Line Items]
Total revenue from external customers											0		0		61
Depreciation and amortization											0		0		0
Equity in earnings of equity method investees											0		0		0
Interest income (expense)											(206)		(50)		(19)
Interest and related charges (benefit)											(206)		(50)		(19)
Income tax expense (benefit)											0		0		0
Net Income (Loss) From Discontinued Operations Including Noncontrolling Interest											0		0		0
Net income (loss) attributable to Dominion Energy											0		0		0
Investment in equity method affiliates	[3]		0				0				0		0
Capital expenditures											0		0		0
Total assets			(4,100)				(5,500)				(4,100)		(5,500)
Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue											0		0		0
Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue											(959)		(859)		(901)
Eliminations
Segment Reporting Information [Line Items]
Operating Revenue											(959)		(859)		(840)
Dominion Energy Virginia | Operating Segments
Segment Reporting Information [Line Items]
Operating Revenue											9,573		9,643		7,976
Total revenue from external customers											9,575		9,658		7,990
Depreciation and amortization											1,622		1,452		1,296
Equity in earnings of equity method investees											0		0		0
Interest income (expense)											15		17		11
Interest and related charges (benefit)											772		645		535
Income tax expense (benefit)											471		514		516
Net Income (Loss) From Discontinued Operations Including Noncontrolling Interest											0		0		0
Net income (loss) attributable to Dominion Energy											1,684		1,905		1,863
Investment in equity method affiliates	[3]		0				0				0		0
Capital expenditures											7,196		5,187		3,756
Total assets			60,700				55,300				60,700		55,300
Dominion Energy Virginia | Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue											(2)		(15)		(14)
Dominion Energy South Carolina | Operating Segments
Segment Reporting Information [Line Items]
Operating Revenue											3,375		3,330		2,975
Total revenue from external customers											3,369		3,323		2,968
Depreciation and amortization											531		507		486
Equity in earnings of equity method investees											0		0		(3)
Interest income (expense)											6		6		10
Interest and related charges (benefit)											249		220		206
Income tax expense (benefit)											79		132		125
Net Income (Loss) From Discontinued Operations Including Noncontrolling Interest											0		0		0
Net income (loss) attributable to Dominion Energy											377		505		437
Investment in equity method affiliates	[3]		0				0				0		0
Capital expenditures											957		708		694
Total assets			17,300				17,200				17,300		17,200
Dominion Energy South Carolina | Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue											6		7		7
Contracted Energy | Operating Segments
Segment Reporting Information [Line Items]
Operating Revenue											851		902		1,084
Total revenue from external customers											835		884		1,017
Depreciation and amortization											105		123		176
Equity in earnings of equity method investees											(34)		2		(2)
Interest income (expense)											96		75		81
Interest and related charges (benefit)											44		18		44
Income tax expense (benefit)											15		55		47
Net Income (Loss) From Discontinued Operations Including Noncontrolling Interest											0		0		0
Net income (loss) attributable to Dominion Energy											99		188		226
Investment in equity method affiliates	[3]		80				103				80		103
Capital expenditures											740		683		420
Total assets			9,100				8,200				9,100		8,200
Contracted Energy | Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue											16		18		67
Corporate and Other | Operating Segments
Segment Reporting Information [Line Items]
Operating Revenue											1,553		922		224
Total revenue from external customers											614		73		(617)
Depreciation and amortization											322		360		159
Equity in earnings of equity method investees											8		19		20
Interest income (expense)											196		61		12
Interest and related charges (benefit)											815		169		489
Income tax expense (benefit)											10		(588)		(869)
Net Income (Loss) From Discontinued Operations Including Noncontrolling Interest											(163)		894		1,358
Net income (loss) attributable to Dominion Energy											(166)		(1,277)		873
Investment in equity method affiliates	[3]		188				192				188		192
Capital expenditures											1,342		1,180		1,191
Total assets			$ 26,000				$ 29,600				26,000		29,600
Corporate and Other | Intersegment revenue
Segment Reporting Information [Line Items]
Operating Revenue											$ 939		$ 849		$ 841

[1] Includes income tax expense of $1.3 billion, $197 million and $374 million for the years ended December 31, 2023, 2022 and 2021, respectively.

[2] See Note 9 for amounts attributable to related parties.

[3] Excludes liability to Atlantic Coast Pipeline.