Operating Revenue (Schedule of Operating Revenue) (Detail) - USD ($) $ in Millions		3 Months Ended		6 Months Ended
		Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		$ 3,794	$ 3,084	$ 8,341	$ 6,924
Other revenues	[1],[2]	(198)	(46)	(466)	(16)
Total operating revenue		3,596	3,038	7,875	6,908
Regulated Electric Sales | Residential
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		1,117	1,017	2,404	2,172
Regulated Electric Sales | Commercial
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		1,089	761	1,987	1,480
Regulated Electric Sales | Industrial
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		220	175	417	353
Regulated Electric Sales | Government and Other Retail
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		297	223	569	412
Regulated Electric Sales | Wholesale
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		68	36	115	79
Nonregulated Electric Sales
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		236	229	603	483
Regulated Gas Sales | Residential
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		231	188	1,000	818
Regulated Gas Sales | Commercial
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		106	79	379	285
Regulated Gas Sales | Other
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		51	23	96	57
Nonregulated Gas Sales
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		4	15	5	67
Regulated Gas Transportation and Storage
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		241	219	538	490
Other Regulated Revenues
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		73	74	119	140
Other Nonregulated Revenues
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers	[3]	61	45	109	88
Virginia Electric and Power Company
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		2,239	1,723	4,435	3,530
Other revenues	[1],[4]	(64)	18	(93)	41
Total operating revenue		2,175	1,741	4,342	3,571
Virginia Electric and Power Company | Regulated Electric Sales | Residential
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		816	748	1,831	1,637
Virginia Electric and Power Company | Regulated Electric Sales | Commercial
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		874	564	1,591	1,111
Virginia Electric and Power Company | Regulated Electric Sales | Industrial
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		110	83	213	174
Virginia Electric and Power Company | Regulated Electric Sales | Government and Other Retail
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		281	208	539	384
Virginia Electric and Power Company | Regulated Electric Sales | Wholesale
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		31	22	63	48
Virginia Electric and Power Company | Nonregulated Electric Sales
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		31	9	45	14
Virginia Electric and Power Company | Other Regulated Revenues
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		80	71	131	128
Virginia Electric and Power Company | Other Nonregulated Revenues
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers	[3],[4]	$ 16	$ 18	$ 22	$ 34

[1] Includes alternative revenue of $40 million and $25 million at Dominion Energy and $19 million and $18 million at Virginia Power for the three months ended June 30, 2022 and 2021, respectively, and $70 million and $47 million at Dominion Energy and $27 million and $38 million at Virginia Power for the six months ended June 30, 2022 and 2021, respectively.

[2] Includes revenue associated with services provided to discontinued operations of $1 million and $2 million for the three and six months ended June 30, 2021, respectively.

[3] Includes sales which are considered to be goods transferred at a point in time of $14 million and $8 million for the three months ended June 30, 2022 and 2021, respectively, and $25 million and $15 million for the six months ended June 30, 2022 and 2021, respectively, at Dominion Energy, primarily consisting of sales of commodities related to nonregulated extraction activities and other miscellaneous products. Additionally, sales of renewable energy credits were $7 million for both the three months ended June 30, 2022 and 2021, and $11 million and $13 million for the six months ended June 30, 2022 and 2021, respectively, at Dominion Energy and less than $1 million and $5 million for the three months ended June 30, 2022 and 2021, respectively, and less than $1 million and $9 million for the six months ended June 30, 2022 and 2021, respectively, at Virginia Power.

[4] See Note 19 for amounts attributable to affiliates.