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

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Namespace Prefix:	us-gaap_
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- 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

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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

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Data Type:	xbrli:monetaryItemType
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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

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Acquisitions and Dispositions (Results of Operations and Pro Forma Information) (Narrative) (Detail) - SCANA - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2019	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Business Acquisition [Line Items]
Increase in operating revenue		$ 3,300	$ 3,100
Increase (decrease) in net income		277	(1,100)
Merger and integration-related costs	$ 1,300		427
Dominion Energy
Business Acquisition [Line Items]
Merger and integration-related costs		$ 97	646
Dominion Energy \| Voluntary Retirement Program
Business Acquisition [Line Items]
Merger and integration-related costs			427
Dominion Energy \| Other Operations and Maintenance
Business Acquisition [Line Items]
Merger and integration-related costs			210	$ 27
Dominion Energy \| Interest and Related Charges
Business Acquisition [Line Items]
Merger and integration-related costs			$ 9