XML 63 R108.htm IDEA: XBRL DOCUMENT
v3.19.3

Regulatory Assets and Liabilities (Schedule of Regulatory Assets) (Detail) - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Mar. 31, 2019 | Sep. 30, 2019 | Dec. 31, 2018
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-current |  |  | $ 966 | $ 496 | [1]
Regulatory assets-noncurrent |  |  | 7,669 | 2,676 | [1]
Total regulatory assets |  |  | $ 8,635 | 3,172 |
Weighted Average |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Weighted average useful life |  |  | 27 years |  |
SCANA |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Electric service customers over period |  |  | 20 years |  |
DESC |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Debt issuance costs |  | $ 270 |  |  |
Virginia Electric and Power Company |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-current | [2] |  | $ 469 | 424 |
Regulatory assets-noncurrent |  |  | 1,917 | 737 | [3]
Total regulatory assets |  |  | 2,386 | 1,161 |
Excess deferred taxes adjusted in charge of operating revenue |  |  | 29 |  |
Excess deferred taxes adjusted in charge of operating revenue net of tax |  |  | 22 |  |
Write off of regulatory asset |  | 17 | 17 |  |
Write off of regulatory asset, after tax |  | $ 13 | $ 13 |  |
Virginia Electric and Power Company | Weighted Average |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Weighted average useful life |  |  | 24 years |  |
Dominion Energy Gas Holdings, LLC |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-current | [4] |  | $ 10 | 8 |
Regulatory assets-noncurrent | [5] |  | 46 | 52 |
Total regulatory assets |  |  | 56 | 60 |
Regulatory assets not expect to earn return |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-current | [6] |  | 78 | 174 |
Regulatory assets-noncurrent | [6] |  |  | 83 |
Regulatory assets not expect to earn return | Virginia Electric and Power Company |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-current | [7] |  | 78 | 174 |
Regulatory assets-noncurrent | [7] |  |  | 83 |
Deferred project costs and DSM programs for gas utilities |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-current | [8] |  | 29 | 17 |
Unrecovered gas costs |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-current | [9] |  | 118 | 14 |
Unrecovered gas costs | Dominion Energy Gas Holdings, LLC |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-current | [9] |  | 2 | 1 |
Deferred rate adjustment clause costs for Virginia electric utility |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-current | [10],[11] |  | 226 | 78 |
Regulatory assets-noncurrent | [10],[11],[12] |  | 88 | 230 |
Deferred nuclear refueling outage costs |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-current | [13] |  | 50 | 69 |
Deferred nuclear refueling outage costs | Virginia Electric and Power Company |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-current | [13] |  | 50 | 69 |
PJM transmission rates |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-current | [14] |  | 69 | 45 |
Regulatory assets-noncurrent | [14] |  | 169 | 192 |
PJM transmission rates | Virginia Electric and Power Company |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-current | [14] |  | 69 | 45 |
Regulatory assets-noncurrent | [14] |  | 169 | 192 |
Other |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-current |  |  | 258 | 99 |
Regulatory assets-noncurrent |  |  | 549 | 125 |
Other | Virginia Electric and Power Company |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-current |  |  | 46 | 58 |
Regulatory assets-noncurrent |  |  | 102 | 54 |
Other | Dominion Energy Gas Holdings, LLC |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-current |  |  | 8 | 7 |
Regulatory assets-noncurrent |  |  | 10 | 4 |
NND Project Costs |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-current | [15] |  | 138 |  |
Regulatory assets-noncurrent | [15] |  | 2,537 |  |
Unrecognized pension and other postretirement benefit costs |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-noncurrent | [16] |  | 1,331 | 1,497 |
Unrecognized pension and other postretirement benefit costs | Dominion Energy Gas Holdings, LLC |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-noncurrent | [17] |  | 4 | 15 |
Deferred project costs for gas utilities |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-noncurrent | [8] |  | 482 | 335 |
Interest rate hedges |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-noncurrent | [18] |  | 897 | 184 |
Interest rate hedges | Virginia Electric and Power Company |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-noncurrent | [19] |  | 555 | 151 |
Interest rate hedges | Dominion Energy Gas Holdings, LLC |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-noncurrent | [20] |  | 32 | 33 |
AROs and related funding |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-noncurrent | [21] |  | $ 330 |  |
Amortization period for deferred costs |  |  | 106 years |  |
Cost of reacquired debt |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-noncurrent | [22],[23] |  | $ 283 | 3 |
Ash pond and landfill closure costs |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-noncurrent | [24] |  | $ 1,003 | 27 |
Regulatory assets expected collection period commencing year |  |  | 2021 |  |
Ash pond and landfill closure costs | Maximum [Member] |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets amounts expected collection period |  |  | 18 years |  |
Ash pond and landfill closure costs | Minimum |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets amounts expected collection period |  |  | 15 years |  |
Ash pond and landfill closure costs | Virginia Electric and Power Company |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-noncurrent | [25] |  | $ 1,003 | 27 |
Regulatory assets expected collection period commencing year |  |  | 2021 |  |
Ash pond and landfill closure costs | Virginia Electric and Power Company | Maximum [Member] |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets amounts expected collection period |  |  | 18 years |  |
Ash pond and landfill closure costs | Virginia Electric and Power Company | Minimum |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets amounts expected collection period |  |  | 15 years |  |
Deferred Project Costs | Maximum [Member] |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Amortization period for deferred costs |  |  | 18 months |  |
Deferred Project Costs | Virginia Electric and Power Company | Maximum [Member] |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Amortization period for deferred costs |  |  | 18 months |  |
Cost of reacquired debt |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Amortization period for deferred costs |  |  | 26 years |  |
Deferred rate adjustment clause costs | Virginia Electric and Power Company |  |  |  |  |
Regulatory Assets [Line Items] |  |  |  |  |
Regulatory assets-current | [10],[11] |  | $ 226 | 78 |
Regulatory assets-noncurrent | [10],[11],[12] |  | $ 88 | $ 230 |
[1] | Dominion Energy’s Consolidated Balance Sheet at December 31, 2018 has been derived from the audited Consolidated Balance Sheet at that date.
[2] | Current regulatory assets are presented in other current assets in Virginia Power’s Consolidated Balance Sheets.
[3] | Virginia Power’s Consolidated Balance Sheet at December 31, 2018 has been derived from the audited Consolidated Balance Sheet at that date.
[4] | Current regulatory assets are presented in other current assets in Dominion Energy Gas’ Consolidated Balance Sheets.
[5] | Noncurrent regulatory assets are presented in other deferred charges and other assets in Dominion Energy Gas’ Consolidated Balance Sheets.
[6] | Reflects deferred fuel expenses for the Virginia, North Carolina and South Carolina jurisdictions of Dominion Energy’s electric generation operations.
[7] | Reflects deferred fuel expenses for the Virginia and North Carolina jurisdictions of Virginia Power’s generation operations.
[8] | Primarily reflects amounts expected to be collected from or owed to gas customers in Dominion Energy’s service territories associated with current and prospective rider projects, including CEP, PIR and pipeline integrity management. See Note 13 for more information.
[9] | Reflects unrecovered or overrecovered gas costs at regulated gas operations, which are recovered or refunded through filings with the applicable regulatory authority.
[10] | As a result of actions from the Virginia Commission in the first quarter of 2019 regarding the ratemaking treatment of excess deferred taxes from the adoption of the 2017 Tax Reform Act for all existing rate adjustment clauses, Virginia Power recorded a $29 million ($22 million after-tax) charge in operating revenue in the Consolidated Statements of Income for amounts which are probable of being returned to customers.
[11] | Reflects deferrals under Virginia Power’s electric transmission FERC formula rate and the deferral of costs associated with certain current and prospective rider projects, net of income taxes refundable from the 2017 Tax Reform Act for Virginia Power. See Note 13 for more information.
[12] | During the first quarter of 2019, Virginia Power recorded a charge of $17 million ($13 million after-tax) to write-off the balance of a regulatory asset for which it is no longer seeking recovery.
[13] | Legislation enacted in Virginia in April 2014 requires Virginia Power to defer operation and maintenance costs incurred in connection with the refueling of any nuclear-powered generating plant. These deferred costs will be amortized over the refueling cycle, not to exceed 18 months.
[14] | Reflects amounts to be recovered through retail rates in Virginia for payments Virginia Power will make to PJM over a ten-year period ending 2028 under the terms of a FERC settlement agreement in May 2018 resolving a PJM cost allocation matter.
[15] | Reflects expenditures by DESC associated with the NND Project, which pursuant to the SCANA Merger Approval Order, will be recovered from DESC electric service customers over a 20-year period ending in 2039. See Note 3 for more information.
[16] | Represents unrecognized pension and other postretirement employee benefit costs expected to be recovered or refunded through future rates generally over the expected remaining service period of plan participants by certain of Dominion Energy’s rate-regulated subsidiaries.
[17] | Represents unrecognized pension and other postretirement employee benefit costs expected to be recovered or refunded through future rates generally over the expected remaining service period of plan participants by certain of Dominion Energy Gas’ rate-regulated subsidiaries.
[18] | Reflects interest rate hedges recoverable from or refundable to customers. Certain of these instruments are settled and any related payments are being amortized into interest expense over the life of the related debt, which has a weighted-average useful life of approximately 27 years as of September 30, 2019.
[19] | Reflects interest rate hedges recoverable from or refundable to customers. Certain of these instruments are settled and any related payments are being amortized into interest expense over the life of the related debt, which has a weighted-average useful life of approximately 24 years as of September 30, 2019.
[20] | Reflects interest rate hedges recoverable from or refundable to customers. Certain of these instruments are settled and any related payments are being amortized into interest expense over the life of the related debt, which has a weighted average useful life of approximately 30 years.
[21] | Represents deferred depreciation and accretion expense related to legal obligations associated with the future retirement of generation, transmission and distribution properties. The AROs primarily relate to DESC’s electric generating facilities, including V.C. Summer nuclear power station, and are expected to be recovered over the related property lives and periods of decommissioning which may range up to approximately 106 years.
[22] | Costs of the reacquisition of debt are deferred and amortized as interest expense over the would-be remaining life of the reacquired debt. The reacquired debt costs had a weighted-average life of approximately 26 years as of September 30, 2019.
[23] | During 2019, DESC purchased certain of its first mortgage bonds as discussed in Note 17. As a result of these transactions, DESC incurred net costs, including write-offs of unamortized discount, premium and debt issuance costs, of $270 million.
[24] | Primarily reflects legislation enacted in Virginia in March 2019 which requires any CCR unit located at certain Virginia Power stations to be closed by removing the CCRs to an approved landfill or through recycling for beneficial reuse. Subject to approval by the Virginia Commission, amounts are expected to be collected over a period between 15 and 18 years commencing no earlier than 2021. See Note 18 for additional information.
[25] | Primarily reflects legislation enacted in Virginia in March 2019 which requires any CCR unit located at certain Virginia Power stations to be closed by removing the CCR to an approved landfill or through recycling for beneficial reuse. Subject to approval by the Virginia Commission, amounts are expected to be collected over a period between 15 and 18 years commencing no earlier than 2021. See Note 18 for additional information.

X
- Definition Electric service customers over period. + References No definition available. + Details
Name: | d_ElectricServiceCustomersOverPeriod
Namespace Prefix: | d_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Excess deferred taxes adjusted in charge of operating revenue. + References No definition available. + Details
Name: | d_ExcessDeferredTaxesAdjustedInChargeOfOperatingRevenue
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Excess deferred taxes adjusted in charge of operating revenue net of tax. + References No definition available. + Details
Name: | d_ExcessDeferredTaxesAdjustedInChargeOfOperatingRevenueNetOfTax
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Regulatory assets, amounts expected collection period. + References No definition available. + Details
Name: | d_RegulatoryAssetsAmountsExpectedCollectionPeriod
Namespace Prefix: | d_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Regulatory assets expected collection period commencing year. + References No definition available. + Details
Name: | d_RegulatoryAssetsExpectedCollectionPeriodCommencingYear
Namespace Prefix: | d_
Data Type: | xbrli:gYearItemType
Balance Type: | na
Period Type: | duration

X
- Definition Write off of regulatory asset. + References No definition available. + Details
Name: | d_WriteOffOfRegulatoryAsset
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Write off of regulatory asset net of tax. + References No definition available. + Details
Name: | d_WriteOffOfRegulatoryAssetNetOfTax
Namespace Prefix: | d_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | us-gaap_DebtInstrumentTerm
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.17) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 835 -SubTopic 30 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=114775744&loc=d3e28555-108399 + Details
Name: | us-gaap_DeferredFinanceCostsNet
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amortization period for the recovery of regulatory asset, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References No definition available. + Details
Name: | us-gaap_RegulatoryAssetAmortizationPeriod
Namespace Prefix: | us-gaap_
Data Type: | xbrli:durationItemType
Balance Type: | na
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_RegulatoryAssetLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The amount for the individual regulatory asset as itemized in a table of regulatory assets as of the end of the period. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
Name: | us-gaap_RegulatoryAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are expected to be recovered through revenue sources within one year or the normal operating cycle, if longer. Such costs are capitalized if they meet both of the following criteria: a. It is probable that future revenue in an amount at least equal to the capitalized cost will result from inclusion of that cost in allowable costs for rate-making purposes. b. Based on available evidence, the future revenue will be provided to permit recovery of the previously incurred cost rather than to provide for expected levels of similar future costs. If the revenue will be provided through an automatic rate-adjustment clause, this criterion requires that the regulator's intent clearly be to permit recovery of the previously incurred cost. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
Name: | us-gaap_RegulatoryAssetsCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Carrying amount as of the balance sheet date of capitalized costs of regulated entities that are not expected to be recovered through revenue sources within one year or the normal operating cycle if longer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 980 -SubTopic 340 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6499975&loc=d3e44250-110382 + Details
Name: | us-gaap_RegulatoryAssetsNoncurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=d_SCANAMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_BusinessAcquisitionAxis=d_DESCMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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_RegulatoryAssetAxis=d_DeferredCostOfFuelUsedInElectricGenerationMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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

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