Gain (loss) on disposition of property plant and equipment, net of tax.

No definition available.

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- Definition

Gas and oil area, developed, net, remaining interest conveyed, percentage.

+ References

No definition available.

+ Details

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- Definition

Oil and gas property, number of natural gas storage fields.

+ References

No definition available.

+ Details

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- Definition

Significant acquisitions and disposals period for payments related to conveyance of natural gas storage fields.

+ References

No definition available.

+ Details

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- Definition

Area assigned to productive oil and gas wells representing summation of fractional ownership working interest to whole.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher SEC
-Name Regulation S-K (SK)
-Number 229
-Section 1208
-Paragraph (a)

+ Details

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- Definition

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 30
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6613-128477

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
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-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
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-Topic 805
-SubTopic 30
-Section 30
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477

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- Definition

Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation.

+ References

No definition available.

+ Details

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- Definition

Amount of gain (loss) on sale or disposal of property, plant and equipment assets, including oil and gas property and timber property.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3602-108585

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- Definition

The cash inflow from the sale of long-lived, physical assets that are used in the normal conduct of business to produce goods and services and not intended for resale.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 12
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3179-108585

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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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Property Plant and Equipment (Narrative) (Detail) - Dominion Energy Gas Holdings, LLC - Oil and Gas Properties $ in Millions	1 Months Ended							3 Months Ended
	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($) a field	Mar. 31, 2018 USD ($) a field	Feb. 28, 2018 USD ($)	Jan. 31, 2018 a	Aug. 31, 2017 USD ($) a	Dec. 31, 2013 USD ($) a	Dec. 31, 2017 USD ($)	Nov. 30, 2014 a field
Marcellus Shale
Property Plant And Equipment [Line Items]
Development rights (number of acres) \| a		9,000			18,000		100,000		24,000
Amount of consideration		$ 6		$ 28
Period for payments related to conveyance of natural gas storage fields							9 years
Gas and oil area developed net remaining interest conveyed percentage					50.00%
Gain on sale		6
After tax gain on sale		$ 4
Number of natural gas storage fields \| field		1							1
Marcellus Shale \| Other operations and maintenance
Property Plant And Equipment [Line Items]
Gain on sale				28
After tax gain on sale				$ 20
Marcellus Shale \| Maximum [Member]
Property Plant And Equipment [Line Items]
Amount of consideration							$ 200
Marcellus Shale \| Amended Agreement to Extend Conveyance of Development Rights
Property Plant And Equipment [Line Items]
Development rights (number of acres) \| a						70,000
Gas and oil area developed net remaining interest conveyed percentage						68.00%
Total consideration	$ 65					$ 130		$ 65
Marcellus Shale \| Final Conveyance \| Amended Agreement to Extend Conveyance of Development Rights
Property Plant And Equipment [Line Items]
Gain on sale	65
After tax gain on sale	$ 47
Utica and Point Pleasant Shale
Property Plant And Equipment [Line Items]
Development rights (number of acres) \| a			11,000
Amount of consideration			$ 16
Gain on sale			16
After tax gain on sale			$ 12
Number of natural gas storage fields \| field			1
Proceeds from assignment of Shale Development Rights			$ 16