Operating Segments (Schedule of Segment Reporting Information, by Segment, Virginia Power) (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
Interest income											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)			273	157	583	981	344	735	(447)	689	1,994		1,321		3,399
Capital expenditures											10,235		7,758		6,061
Total assets			109,032				104,795				109,032		104,795
Virginia Electric and Power Company
Segment Reporting Information [Line Items]
Operating Revenue			2,292	2,645	2,252	2,384	2,436	2,875	2,176	2,167	9,573	[1]	9,654	[1]	7,470	[1]
Depreciation and amortization											1,871		1,736		1,364
Interest income											15		17		11
Interest and related charges (benefit)	[1]										764		642		534
Income tax expense (benefit)											389		294		447
Net income (loss)			288	$ 475	$ 334	$ 355	218	$ 516	$ 42	$ 336	1,452		1,112		1,662
Capital expenditures											7,196		5,187		3,756
Total assets			58,618				53,194				58,618		53,194
Virginia Electric and Power Company | Dominion Energy Virginia
Segment Reporting Information [Line Items]
Operating Revenue											9,573		9,643		7,976
Depreciation and amortization											1,622		1,452		1,296
Interest income											15		17		11
Interest and related charges (benefit)											772		645		535
Income tax expense (benefit)											471		514		516
Net income (loss)											1,684		1,905		1,863
Capital expenditures											7,196		5,187		3,756
Total assets			58,600				53,200				58,600		53,200
Virginia Electric and Power Company | Corporate and Other
Segment Reporting Information [Line Items]
Operating Revenue											0		11		(506)
Depreciation and amortization											249		284		68
Interest income											0		0		0
Interest and related charges (benefit)											(8)		(3)		(1)
Income tax expense (benefit)											(82)		(220)		(69)
Net income (loss)											(232)		(793)		(201)
Capital expenditures											0		0		$ 0
Total assets			$ 0				$ 0				$ 0		$ 0

[1] See Note 25 for amounts attributable to affiliates.