Regulatory Matters - Summary of Virginia Power Electric Transmission Project Applied (Detail) - Virginia Electric and Power Company $ in Millions	12 Months Ended
	Dec. 31, 2023 USD ($) mi kV
Construct new switching station, substations, transmission lines and related projects in Lunenberg and Mecklenburg Counties Virginia
Public Utilities General Disclosures [Line Items]
Application Date	2022-10
Approval Date	2023-06
Type of Line | kV	230
Miles of Lines | mi	18
Cost Estimate | $	$ 230	[1]
Construct new switching station, substation, transmission lines and related projects in Charlotte, Halifax and Mecklenburg Counties, Virginia
Public Utilities General Disclosures [Line Items]
Application Date	2022-10
Approval Date	2023-05
Type of Line | kV	230
Miles of Lines | mi	26
Cost Estimate | $	$ 215	[1]
Construct new Mars and Wishing Star substations, transmission lines and related projects in Loudoun County, Virginia
Public Utilities General Disclosures [Line Items]
Application Date	2022-10
Approval Date	2023-04
Type of Line	500/230 kV
Miles of Lines | mi	4
Cost Estimate | $	$ 720	[1]
Construct new Cirrus and Keyser switching stations, transmission lines and related projects in Culpeper, Virginia
Public Utilities General Disclosures [Line Items]
Application Date	2022-11
Approval Date	2023-10
Type of Line | kV	230
Miles of Lines | mi	5
Cost Estimate | $	$ 65	[1]
Rebuild of Lines #2019 and #2007 in the City of Virginia Beach, Virginia
Public Utilities General Disclosures [Line Items]
Application Date	2023-02
Approval Date	2023-08
Type of Line | kV	230
Miles of Lines | mi	5
Cost Estimate | $	$ 95	[1]
Construct new transmission lines and convert Jeffress switching station in Mecklenburg County, Virginia
Public Utilities General Disclosures [Line Items]
Application Date	2023-05
Approval Date	2024-01
Type of Line | kV	230
Miles of Lines | mi	18
Cost Estimate | $	$ 135	[1]
Construct new Germanna substation, transmission line and related projects in Culpeper County, Virginia
Public Utilities General Disclosures [Line Items]
Application Date	2023-11
Type of Line | kV	230
Miles of Lines | mi	2
Cost Estimate | $	$ 55	[1]
Construct Daves Store transmission line extension in Prince William County, Virginia
Public Utilities General Disclosures [Line Items]
Application Date	2024-02
Type of Line | kV	230
Miles of Lines | mi	3
Cost Estimate | $	$ 70	[1]

[1] Represents the cost estimate included in the application except as updated in the approval if applicable. In addition, Virginia Power had various other transmission projects approved during 2023 and early 2024 or applied for and currently pending approval with aggregate cost estimates of approximately $155 million and $145 million, respectively.