XML 59 R100.htm IDEA: XBRL DOCUMENT
v3.19.3

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 |  |  |  |  |  |

X
- Definition Gain (loss) on disposition of property plant and equipment, net of tax. + References No definition available. + Details
Name: | d_GainLossOnDispositionOfPropertyPlantAndEquipmentNetOfTax
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Gas and oil area, developed, net, remaining interest conveyed, percentage. + References No definition available. + Details
Name: | d_GasAndOilAreaDevelopedNetRemainingInterestConveyedPercentage
Namespace Prefix: | d_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Oil and gas property, number of natural gas storage fields. + References No definition available. + Details
Name: | d_OilAndGasPropertyNumberOfNaturalGasStorageFields
Namespace Prefix: | d_
Data Type: | xbrli:integerItemType
Balance Type: | na
Period Type: | instant

X
- Definition Significant acquisitions and disposals period for payments related to conveyance of natural gas storage fields. + References No definition available. + Details
Name: | d_SignificantAcquisitionsAndDisposalsPeriodForPaymentsRelatedToConveyanceOfNaturalGasStorageFields
Namespace Prefix: | d_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- 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
Name: | srt_GasAndOilAreaDevelopedNet
Namespace Prefix: | srt_
Data Type: | num:areaItemType
Balance Type: | na
Period Type: | instant

X
- 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 -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35744584&loc=d3e6927-128479 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 805 -SubTopic 30 -Section 30 -Paragraph 7 -URI http://asc.fasb.org/extlink&oid=116859721&loc=d3e6578-128477 + Details
Name: | us-gaap_BusinessCombinationConsiderationTransferred1
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of consideration received or receivable for the disposal of assets and liabilities, including discontinued operation. + References No definition available. + Details
Name: | us-gaap_DisposalGroupIncludingDiscontinuedOperationConsideration
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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 + Details
Name: | us-gaap_GainLossOnSaleOfPropertyPlantEquipment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- 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 + Details
Name: | us-gaap_ProceedsFromSaleOfPropertyPlantAndEquipment
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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_PropertyPlantAndEquipmentLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | dei_LegalEntityAxis=d_DominionEnergyGasHoldingsLLCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementGeographicalAxis=d_MarcellusShaleMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_OilAndGasPropertiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | srt_RangeAxis=srt_MaximumMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ResearchAndDevelopmentArrangementContractToPerformForOthersByTypeAxis=d_AmendedAgreementToExtendConveyanceOfDevelopmentRightsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_TransactionTypeAxis=d_FinalConveyanceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_StatementGeographicalAxis=d_UticaAndPointPleasantShaleMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |