Acquisitions and Dispositions (Results of Operations and Pro Forma Information) (Narrative) (Detail) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2019
Dominion Energy
Business Acquisition [Line Items]
Merger and integration related costs	$ 10,000,000	$ 14,000,000
SCANA
Business Acquisition [Line Items]
Increase in operating revenue	909,000,000	1,100,000,000
Decrease in net income	102,000,000	1,200,000,000
Merger and integration related costs		548,000,000
SCANA \| Dominion Energy
Business Acquisition [Line Items]
Merger and integration related costs	443,000,000	567,000,000
SCANA \| Dominion Energy \| Voluntary Retirement Program
Business Acquisition [Line Items]
Merger and integration related costs	423,000,000	423,000,000
SCANA \| Dominion Energy \| Other operations and maintenance
Business Acquisition [Line Items]
Merger and integration related costs	20,000,000	135,000,000
SCANA \| Dominion Energy \| Interest and related charges
Business Acquisition [Line Items]
Merger and integration related costs	$ 0	$ 9,000,000

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.

No definition available.

+ Details

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

- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 23
-URI http://asc.fasb.org/extlink&oid=116868678&loc=d3e1043-128460

+ Details

Name:	us-gaap_BusinessCombinationAcquisitionRelatedCosts
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

This element represents the amount of earnings or loss of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

+ Details

Name:	us-gaap_BusinessCombinationProFormaInformationEarningsOrLossOfAcquireeSinceAcquisitionDateActual
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

This element represents the amount of revenue of the acquiree since the acquisition date included in the consolidated income statement for the reporting period.

+ References

+ Details

Name:	us-gaap_BusinessCombinationProFormaInformationRevenueOfAcquireeSinceAcquisitionDateActual
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Details

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

- Details

Name:	us-gaap_BusinessAcquisitionAxis=d_SCANAMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RetirementPlanNameAxis=d_VoluntaryRetirementProgramMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementLocationAxis=d_OtherOperationsAndMaintenanceExpenseMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementLocationAxis=d_InterestAndRelatedChargesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: