Operating Revenue (Schedule of Operating Revenue) (Detail) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		$ 3,758	$ 4,236	$ 10,290	$ 10,967
Other revenues	[1],[2]	52	(273)	569	(832)
Total operating revenue		3,810	3,963	10,859	10,135
Regulated Electric Sales | Residential
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		1,558	1,609	3,968	4,013
Regulated Electric Sales | Commercial
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		1,236	1,349	3,453	3,336
Regulated Electric Sales | Industrial
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		227	253	658	670
Regulated Electric Sales | Government and Other Retail
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		288	353	764	922
Regulated Electric Sales | Wholesale
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		53	66	133	181
Nonregulated Electric Sales
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		229	345	611	948
Regulated Gas Sales | Residential
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		28	32	207	247
Regulated Gas Sales | Commercial
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		25	36	106	141
Regulated Gas Sales | Other
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		19	55	58	132
Regulated Gas Transportation and Storage
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		4	11	13	35
Other Regulated Revenues
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		61	68	204	208
Other Nonregulated Revenues
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers	[2],[3]	30	59	115	134
Virginia Electric and Power Company
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		2,598	2,959	7,133	7,394
Other revenues	[1],[2]	47	(84)	147	(177)
Total operating revenue		2,645	2,875	7,280	7,217
Virginia Electric and Power Company | Regulated Electric Sales | Residential
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		1,133	1,238	2,975	3,069
Virginia Electric and Power Company | Regulated Electric Sales | Commercial
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		962	1,105	2,745	2,696
Virginia Electric and Power Company | Regulated Electric Sales | Industrial
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		109	134	324	347
Virginia Electric and Power Company | Regulated Electric Sales | Government and Other Retail
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		269	335	711	874
Virginia Electric and Power Company | Regulated Electric Sales | Wholesale
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		37	38	88	101
Virginia Electric and Power Company | Nonregulated Electric Sales
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		22	17	55	62
Virginia Electric and Power Company | Other Regulated Revenues
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		57	64	193	195
Virginia Electric and Power Company | Other Nonregulated Revenues
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers	[2],[3]	$ 9	$ 28	$ 42	$ 50

[1] Includes alternative revenue of $34 million and $20 million for the three months ended September 30, 2023 and 2022, respectively, and $111 million and $47 million for the nine months ended September 30, 2023 and 2022, respectively, at both Dominion Energy and Virginia Power.

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

[3] Includes sales of renewable energy credits were $7 million and $21 million for the three months ended September 30, 2023 and 2022, respectively, and $36 million and $32 million for the nine months ended September 30, 2023 and 2022, respectively, at Dominion Energy and $2 million and $13 million for the three months ended September 30, 2023 and 2022, respectively, and $24 million and $13 million for the nine months ended September 30, 2023 and 2022, respectively, at Virginia Power.