XML 187 R161.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Operating Segments (Narrative) (Detail) - USD ($) $ in Millions | 3 Months Ended | 12 Months Ended
--- | --- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Segment Reporting Information [Line Items] |  |  |  |  |
Tax benefit resulting from remeasurement of deferred income taxes as a result of the 2017 Tax Reform Act | $ (851) |  | $ (851) |  |
Charges associated with equity method investments in wind-powered generation facilities |  |  | 158 |  |
Charges associated with equity method investments in wind-powered generation facilities, after tax | 96 |  |  |  |
Charges associated with future ash pond and landfill closure costs |  |  |  | $ 197 | $ 99
Virginia Electric and Power Company |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Tax benefit resulting from remeasurement of deferred income taxes as a result of the 2017 Tax Reform Act | (93) |  | (93) |  |
Charges associated with future ash pond and landfill closure costs |  |  |  | 197 | 99
Dominion Energy Gas Holdings, LLC |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Tax benefit resulting from remeasurement of deferred income taxes as a result of the 2017 Tax Reform Act | $ (197) |  | (197) |  |
Facilities Subject to Coal Combustion Residual Final Rule |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Charge related to future ash pond and landfill closure costs |  | $ 122 |  |  |
Facilities Subject to Coal Combustion Residual Final Rule | Virginia Electric and Power Company |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Charge related to future ash pond and landfill closure costs |  | $ 121 |  |  |
Operating Segments |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
After-tax net (expenses) benefit |  |  | 861 | (180) | (136)
Tax benefit resulting from remeasurement of deferred income taxes as a result of the 2017 Tax Reform Act |  |  | 979 |  |
Charges associated with equity method investments in wind-powered generation facilities |  |  | 158 |  |
Charges associated with equity method investments in wind-powered generation facilities, after tax |  |  | 96 |  |
Operating Segments | Virginia Electric and Power Company |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Tax benefit resulting from remeasurement of deferred income taxes as a result of the 2017 Tax Reform Act |  |  | 93 |  |
Operating Segments | Dominion Energy Gas Holdings, LLC |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
After-tax net (expenses) benefit |  |  | (174) | (7) | (13)
Tax benefit resulting from remeasurement of deferred income taxes as a result of the 2017 Tax Reform Act |  |  | 185 |  |
Ceiling test impairment charge |  |  |  |  | 16
Ceiling test impairment charge, net of tax |  |  |  |  | 10
Operating Segments | Organizational Design Initiative |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Organizational design initiative charges, after tax |  |  |  | 36 |
Organizational design initiative |  |  |  | 59 |
Operating Segments | Organizational Design Initiative | Dominion Energy Gas Holdings, LLC |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Organizational design initiative charges, after tax |  |  |  | 5 |
Organizational design initiative |  |  |  | 8 |
Operating Segments | Corporate and Other |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
After-tax net (expenses) benefit |  |  | 389 | (484) | (391)
Operating Segments | Corporate and Other | Virginia Electric and Power Company |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
After-tax net (expenses) benefit |  |  | 74 | (173) | (153)
Operating Segments | Corporate and Other | Dominion Energy Gas Holdings, LLC |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
After-tax net (expenses) benefit |  |  | (179) | (3) | (21)
Operating Segments | Dominion Generation | Virginia Regulation | Deferred Fuel Costs |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Write offs of deferred fuel costs |  |  |  |  | 85
Write off of deferred fuel cost, net of tax |  |  |  |  | 52
Operating Segments | Dominion Generation | Virginia Regulation | Deferred Fuel Costs | Virginia Electric and Power Company |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Write offs of deferred fuel costs |  |  |  |  | 85
Write off of deferred fuel cost, net of tax |  |  |  |  | 52
Operating Segments | Dominion Generation | Facilities Subject to Coal Combustion Residual Final Rule |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Charges associated with future ash pond and landfill closure costs |  |  |  | 197 | 99
Charge related to future ash pond and landfill closure costs |  |  |  | 122 | 60
Operating Segments | Dominion Generation | Facilities Subject to Coal Combustion Residual Final Rule | Virginia Electric and Power Company |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Charges associated with future ash pond and landfill closure costs |  |  |  | 197 | 99
Charge related to future ash pond and landfill closure costs |  |  |  | 121 | $ 60
Operating Segments | Gas Infrastructure | Organizational Design Initiative |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Organizational design initiative charges, after tax |  |  | 324 | 12 |
Operating Segments | Power Generation | Organizational Design Initiative |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Organizational design initiative charges, after tax |  |  | $ 655 | 19 |
Operating Segments | Power Delivery | Organizational Design Initiative |  |  |  |  |
Segment Reporting Information [Line Items] |  |  |  |  |
Organizational design initiative charges, after tax |  |  |  | $ 5 |

X
- Definition Environmental remediation expense, net of tax. + References No definition available. + Details
Name: | d_EnvironmentalRemediationExpenseNetOfTax
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Equity method investments charges. + References No definition available. + Details
Name: | d_EquityMethodInvestmentsCharges
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Equity method investments charges net of tax. + References No definition available. + Details
Name: | d_EquityMethodInvestmentsChargesNetOfTax
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Restructuring charges, net of tax. + References No definition available. + Details
Name: | d_RestructuringChargesNetOfTax
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Tax Cuts and Jobs Act of 2017, change in tax rate, income tax expense (benefit). + References No definition available. + Details
Name: | d_TaxCutsAndJobsActOf2017ChangeInTaxRateIncomeTaxExpenseBenefit
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Unamortized Costs Capitalized Less Related Deferred Income Taxes Exceed Ceiling Limitations, Expense, Net of Tax + References No definition available. + Details
Name: | d_UnamortizedCostsCapitalizedLessRelatedDeferredIncomeTaxesExceedCeilingLimitationsExpenseNetOfTax
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Utilities operating expense, impairments, net of tax. + References No definition available. + Details
Name: | d_UtilitiesOperatingExpenseImpairmentsNetOfTax
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The charge against earnings in the period for known or estimated future costs arising from requirements to perform environmental remediation activities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 410 -SubTopic 30 -Section 50 -Paragraph 12 -URI http://asc.fasb.org/extlink&oid=6393242&loc=d3e13296-110859 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 + Details
Name: | us-gaap_EnvironmentalRemediationExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business). + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.7) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
Name: | us-gaap_NonoperatingIncomeExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SAB Topic 5.P.3) -URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140864-122747 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 420 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SAB Topic 5.P.4(b)) -URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747 + Details
Name: | us-gaap_RestructuringCharges
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_SegmentReportingInformationLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The excess of unamortized costs capitalized within a cost center, less related deferred income taxes, over the cost center ceiling limitation, which is charged to expense for oil and gas producing companies that use full cost method of accounting for investments in oil and gas producing properties. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-10(c)(4)(ii)) -URI http://asc.fasb.org/extlink&oid=82851474&loc=d3e511914-122862 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 932 -SubTopic 360 -Section S99 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=27015634&loc=d3e516453-122869 + Details
Name: | us-gaap_UnamortizedCostsCapitalizedLessRelatedDeferredIncomeTaxesExceedCeilingLimitationExpense
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

X
- Definition Amount of operating expense for impairments of regulated operation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 225 -SubTopic 10 -Section S99 -Paragraph 2 -Subparagraph (SX 210.5-03.2(b)) -URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688 + Details
Name: | us-gaap_UtilitiesOperatingExpenseImpairments
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | duration

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

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

X
- Details
Name: | us-gaap_PublicUtilitiesRegulatoryProceedingAxis=d_FacilitiesSubjectToCoalCombustionResidualFinalRuleMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ConsolidationItemsAxis=us-gaap_OperatingSegmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RestructuringPlanAxis=d_OrganizationalDesignInitiativeMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=us-gaap_CorporateAndOtherMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=d_DominionGenerationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAgencyAxis=d_VirginiaRegulationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_RegulatoryAssetAxis=us-gaap_DeferredFuelCostsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=d_GasInfrastructureMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=d_PowerGenerationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementBusinessSegmentsAxis=d_PowerDeliveryMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |