Operating Revenue (Schedule of Operating Revenue) (Parenthetical) (Detail) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		$ 14,170	$ 13,752	$ 13,745
Gas, Transmission & Storage
Public Utilities General Disclosures [Line Items]
Operating revenue		5	4	6
NGL Midstream | Transferred at a Point in Time
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		34	22	37
Renewable Energy Investment Tax Credits
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		33	20	24
Alternative Revenue Programs
Public Utilities General Disclosures [Line Items]
Other revenues		56	119	66
Virginia Electric and Power Company
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		7,470	7,661	8,036
Other revenues	[1],[2]		102	72
Virginia Electric and Power Company | Renewable Energy Investment Tax Credits
Public Utilities General Disclosures [Line Items]
Operating revenue from contracts with customers		21	11	17
Virginia Electric and Power Company | Alternative Revenue Programs
Public Utilities General Disclosures [Line Items]
Other revenues		$ 44	$ 82	$ 52

[1] Includes alternative revenue of $56 million, $119 million and $66 million at Dominion Energy and $44 million, $82 million and $52 million at Virginia Power for years ended December 31, 2021, 2020 and 2019, respectively.

[2] See Notes 9 and 25 for amounts attributable to related parties and affiliates.