XML 147 R144.htm IDEA: XBRL DOCUMENT v3.19.3.a.u2

Regulatory Matters - Summary of Virginia Power Electric Transmission Project Applied (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2019 USD ($) mi kV
Rebuild and operate between Lanexa and the Northern Neck in Virginia
Public Utilities, General Disclosures [Line Items]
Capacity of transmission line (kV) | kV	230
The total estimated capital investment | $	$ 30
Virginia Electric and Power Company | Build a new substation and connect three existing transmission lines thereto in Fluvanna County, Virginia
Public Utilities, General Disclosures [Line Items]
Capacity of transmission line (kV) | kV	230
Virginia Electric and Power Company | Rebuild and operate the Glebe substation and relocate and operate in Arlington County, Virginia and the City of Alexandria, Virginia existing overhead line underground
Public Utilities, General Disclosures [Line Items]
Capacity of transmission line (kV) | kV	230
Virginia Electric and Power Company | Rebuild and operate between Valley, Virginia and Mt. Storm, West Virginia
Public Utilities, General Disclosures [Line Items]
Capacity of transmission line (kV) | kV	500
Virginia Electric and Power Company | Rebuild and operate between the Suffolk and the Virginia/North Carolina state line
Public Utilities, General Disclosures [Line Items]
Capacity of transmission line (kV) | kV	230
Virginia Electric and Power Company | Rebuild and operate five segments between the Loudoun and Ox substations
Public Utilities, General Disclosures [Line Items]
Capacity of transmission line (kV) | kV	230
Virginia Electric and Power Company | Build new switching station and line loop in Loudon County, Virginia (Evergreen Mills)
Public Utilities, General Disclosures [Line Items]
Capacity of transmission line (kV) | kV	230
Virginia Electric and Power Company | Build new substation and line loop in Loudon County, Virginia (Lockridge)
Public Utilities, General Disclosures [Line Items]
Capacity of transmission line (kV) | kV	230
Virginia Electric and Power Company | Virginia Regulation | Rebuild and operate between Lanexa and the Northern Neck in Virginia
Public Utilities, General Disclosures [Line Items]
Application Date	2018-06
Length of kV line (miles) | mi	3
Virginia Electric and Power Company | Virginia Regulation | Build a new substation and connect three existing transmission lines thereto in Fluvanna County, Virginia
Public Utilities, General Disclosures [Line Items]
Approval Date	2019-06
Length of kV line (miles) | mi	1
The total estimated capital investment | $	$ 30
Virginia Electric and Power Company | Virginia Regulation | Rebuild and operate the Glebe substation and relocate and operate in Arlington County, Virginia and the City of Alexandria, Virginia existing overhead line underground
Public Utilities, General Disclosures [Line Items]
Application Date	2019-03
Length of kV line (miles) | mi	1
The total estimated capital investment | $	$ 125
Virginia Electric and Power Company | Virginia Regulation | Rebuild and operate between Valley, Virginia and Mt. Storm, West Virginia
Public Utilities, General Disclosures [Line Items]
Application Date	2019-04
Approval Date	2019-11
Length of kV line (miles) | mi	65
The total estimated capital investment | $	$ 290
Virginia Electric and Power Company | Virginia Regulation | Rebuild and operate between the Suffolk and the Virginia/North Carolina state line
Public Utilities, General Disclosures [Line Items]
Application Date	2019-05
Approval Date	2019-11
Length of kV line (miles) | mi	11
The total estimated capital investment | $	$ 20
Virginia Electric and Power Company | Virginia Regulation | Rebuild and operate five segments between the Loudoun and Ox substations
Public Utilities, General Disclosures [Line Items]
Application Date	2019-08
Approval Date	Pending
Length of kV line (miles) | mi	19
The total estimated capital investment | $	$ 70
Virginia Electric and Power Company | Virginia Regulation | Build new switching station and line loop in Loudon County, Virginia (Evergreen Mills)
Public Utilities, General Disclosures [Line Items]
Approval Date	Pending
Length of kV line (miles) | mi	2
Virginia Electric and Power Company | Virginia Regulation | Build new substation and line loop in Loudon County, Virginia (Lockridge)
Public Utilities, General Disclosures [Line Items]
Application Date	2019-12
Approval Date	Pending
Length of kV line (miles) | mi	1
The total estimated capital investment | $	$ 30
Virginia Electric and Power Company | Virginia Regulation | Rebuild of overhead transmission lines between Chesterfield Substation and Tyler Substation in Chesterfield County, Virginia
Public Utilities, General Disclosures [Line Items]
The total estimated capital investment | $	$ 35

X

- Definition

Application date of public utilities transmission.

+ References

No definition available.

+ Details

Name:	d_ApplicationDateOfPublicUtilitiesTransmission
Namespace Prefix:	d_
Data Type:	xbrli:gYearMonthItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Description of the approval date of public utilities projects.

+ References

No definition available.

+ Details

Name:	d_ApprovalDateOfPublicUtilitiesProjectsDescription
Namespace Prefix:	d_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Approval date of public utilities transmission.

+ References

No definition available.

+ Details

Name:	d_ApprovalDateOfPublicUtilitiesTransmission
Namespace Prefix:	d_
Data Type:	xbrli:gYearMonthItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Kilo Volt Line

+ References

No definition available.

+ Details

Name:	d_KiloVoltLine
Namespace Prefix:	d_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Public utilities, length of transmission line.

+ References

No definition available.

+ Details

Name:	d_PublicUtilitiesLengthOfTransmissionLine
Namespace Prefix:	d_
Data Type:	xbrli:decimalItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Public utilities, property, plant and equipment, expected cost of construction.

+ References

No definition available.

+ Details

Name:	d_PublicUtilitiesPropertyPlantAndEquipmentExpectedCostOfConstruction
Namespace Prefix:	d_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

X

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

Name:	us-gaap_PublicUtilitiesGeneralDisclosuresLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

X

- Details

Name:	us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationByPropertyOrProjectAxis=d_RebuildAndOperateBetweenLanexaAndTheNorthernNeckInVirginiaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	dei_LegalEntityAxis=d_VirginiaElectricAndPowerCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationByPropertyOrProjectAxis=d_BuildANewSubstationAndConnectThreeExistingTransmissionLinesTheretoInFluvannaCountyVirginiaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationByPropertyOrProjectAxis=d_RebuildAndOperateTheGlebeSubstationAndRelocateAndOperateInArlingtonCountyVirginiaAndTheCityOfAlexandriaVirginiaExistingOverheadLineUndergroundMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationByPropertyOrProjectAxis=d_RebuildAndOperateBetweenValleyVirginiaAndMtStormWestVirginiaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationByPropertyOrProjectAxis=d_RebuildAndOperateBetweenTheSuffolkAndTheVirginianorthCarolinaStateLineMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationByPropertyOrProjectAxis=d_RebuildAndOperateFiveSegmentsBetweenTheLoudounAndOxSubstationsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationByPropertyOrProjectAxis=d_BuildNewSwitchingStationAndLineLoopInLoudonCountyVirginiaevergreenMillsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationByPropertyOrProjectAxis=d_BuildNewSubstationAndLineLoopInLoudonCountyVirginialockridgeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_RegulatoryAgencyAxis=d_VirginiaRegulationMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationByPropertyOrProjectAxis=d_RebuildOfOverheadTransmissionLinesBetweenChesterfieldSubstationAndTylerSubstationInChesterfieldCountyVirginiaMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: