Operating Revenue (Schedule of Operating Revenue) (Detail) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		$ 4,655	$ 3,434	$ 12,996	$ 10,358
Other revenues	[1],[2]	(269)	(258)	(735)	(274)
Total operating revenue		4,386	3,176	12,261	10,084
Regulated Electric Sales | Residential
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		1,609	1,281	4,013	3,453
Regulated Electric Sales | Commercial
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		1,349	831	3,336	2,311
Regulated Electric Sales | Industrial
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		253	194	670	547
Regulated Electric Sales | Government and Other Retail
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		353	258	922	670
Regulated Electric Sales | Wholesale
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		66	52	181	131
Nonregulated Electric Sales
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		345	271	948	754
Regulated Gas Sales | Residential
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		154	132	1,154	950
Regulated Gas Sales | Commercial
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		83	61	462	346
Regulated Gas Sales | Other
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		62	31	158	88
Nonregulated Gas Sales
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		2	7	7	74
Regulated Gas Transportation and Storage
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		229	208	767	698
Other Regulated Revenues
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		76	47	195	187
Other Nonregulated Revenues
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers	[3]	74	61	183	149
Virginia Electric and Power Company
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		2,959	1,987	7,394	5,517
Other revenues	[1],[4]	(84)	(11)	(177)	30
Total operating revenue		2,875	1,976	7,217	5,547
Virginia Electric and Power Company | Regulated Electric Sales | Residential
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		1,238	935	3,069	2,572
Virginia Electric and Power Company | Regulated Electric Sales | Commercial
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		1,105	604	2,696	1,715
Virginia Electric and Power Company | Regulated Electric Sales | Industrial
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		134	94	347	268
Virginia Electric and Power Company | Regulated Electric Sales | Government and Other Retail
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		335	241	874	625
Virginia Electric and Power Company | Regulated Electric Sales | Wholesale
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		38	31	101	79
Virginia Electric and Power Company | Nonregulated Electric Sales
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		17	18	62	32
Virginia Electric and Power Company | Other Regulated Revenues
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		64	37	195	165
Virginia Electric and Power Company | Other Nonregulated Revenues
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers	[3],[4]	$ 28	$ 27	$ 50	$ 61

[1] Includes alternative revenue of $20 million and $3 million at Dominion Energy and $20 million and $3 million at Virginia Power for the three months ended September 30, 2022 and 2021, respectively, and $90 million and $50 million at Dominion Energy and $47 million and $41 million at Virginia Power for the nine months ended September 30, 2022 and 2021, respectively.

[2] Includes revenue associated with services provided to discontinued operations of $1 million and $3 million for the three and nine months ended September 30, 2021, respectively.

[3] Includes sales which are considered to be goods transferred at a point in time of $10 million and $9 million for the three months ended September 30, 2022 and 2021, respectively, and $35 million and $24 million for the nine months ended September 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 $21 million and $16 million for the three months ended September 30, 2022 and 2021, respectively, and $32 million and $29 million for the nine months ended September 30, 2022 and 2021, respectively, at Dominion Energy and $13 million for both the three months ended September 30, 2022 and 2021 and $13 million and $22 million for the nine months ended September 30, 2022 and 2021, respectively, at Virginia Power.

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