A description of the principal activities of an investee accounted for under the equity method.

No definition available.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=114001798&loc=d3e33918-111571

+ Details

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- Definition

This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 323
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=109237563&loc=d3e33749-111570

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 25
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=115929826&loc=d3e8813-108599

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.12)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- 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

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Investments (Investments Under Equity Method of Accounting) (Detail) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2019	Feb. 25, 2020	Dec. 31, 2018
Schedule of Equity Method Investments [Line Items]
Investment Balance	$ 1,646		$ 1,278
Atlantic Coast Pipeline
Schedule of Equity Method Investments [Line Items]
Ownership%	48.00%
Investment Balance	$ 1,123		820
Description	Gas transmission system
Iroquois
Schedule of Equity Method Investments [Line Items]
Ownership%	50.00%
Investment Balance	$ 276		302
Description	Gas transmission system
Fowler I Holdings LLC
Schedule of Equity Method Investments [Line Items]
Ownership%	50.00%
Investment Balance	$ 74		82
Description	Wind-powered merchant generation facility
Wrangler
Schedule of Equity Method Investments [Line Items]
Ownership%	20.00%
Investment Balance	$ 77		0
Description	Nonregulated retail energy marketing
Other Investment
Schedule of Equity Method Investments [Line Items]
Investment Balance	$ 96		74
Dominion Energy Gas Holdings, LLC
Schedule of Equity Method Investments [Line Items]
Investment Balance	$ 312		339
Dominion Energy Gas Holdings, LLC \| Atlantic Coast Pipeline
Schedule of Equity Method Investments [Line Items]
Ownership%		53.00%
Dominion Energy Gas Holdings, LLC \| Iroquois
Schedule of Equity Method Investments [Line Items]
Ownership%	50.00%
Investment Balance	$ 276		302
Description	Gas transmission system
Dominion Energy Gas Holdings, LLC \| White Rive Hub
Schedule of Equity Method Investments [Line Items]
Ownership%	50.00%
Investment Balance	$ 36		$ 37
Description	Gas transmission system