XML 91 R74.htm IDEA: XBRL DOCUMENT
v3.20.2

Fair Value Measurements (Fair Value, Option, Quantitative Disclosures) (Detail) $ in Millions | 6 Months Ended |
--- | --- | ---
Jun. 30, 2020 USD ($) $ / MMBTU $ / MWh | Dec. 31, 2019 USD ($)
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Fair Value of Derivative Assets |  | $ 216 | $ 93
Fair Value of Derivative Liabilities |  | 1,334 | 740
Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Fair Value of Derivative Assets |  | 133 | 24
Fair Value of Derivative Liabilities |  | 1,004 | 466
Fair Value, Measurements, Recurring |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Total assets |  | 5,922 | 5,963
Total liabilities |  | 1,334 | 740
Fair Value, Measurements, Recurring | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Total assets |  | 2,764 | 2,748
Total liabilities |  | 1,004 | 466
Fair Value, Measurements, Recurring | Commodity |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Fair Value of Derivative Assets |  | 182 | 74
Fair Value of Derivative Liabilities |  | 50 | 131
Fair Value, Measurements, Recurring | Commodity | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Fair Value of Derivative Assets |  | 133 | 22
Fair Value of Derivative Liabilities |  | 24 | 103
Fair Value, Measurements, Recurring | Level 3 |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Total assets |  | 130 | 19
Total liabilities |  | 7 | 56
Fair Value, Measurements, Recurring | Level 3 | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Total assets |  | 130 | 19
Total liabilities |  | 7 | 56
Fair Value, Measurements, Recurring | Level 3 | Commodity |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Fair Value of Derivative Assets |  | 130 | 19
Fair Value of Derivative Liabilities |  | 7 | 56
Fair Value, Measurements, Recurring | Level 3 | Commodity | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Fair Value of Derivative Assets |  | 130 | 19
Fair Value of Derivative Liabilities |  | 7 | $ 56
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | FTRs [Member] | Commodity |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Fair Value of Derivative Assets |  | 18 |
Fair Value of Derivative Liabilities |  | 5 |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | FTRs [Member] | Commodity | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Fair Value of Derivative Assets |  | 18 |
Fair Value of Derivative Liabilities |  | $ 5 |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | FTRs [Member] | Commodity | Minimum | Derivative Financial Instruments, Liabilities | Market Price [Member] |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MWh | [1] | (5) |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | FTRs [Member] | Commodity | Minimum | Derivative Financial Instruments, Liabilities | Market Price [Member] | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MWh | [1] | (5) |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | FTRs [Member] | Commodity | Minimum | Assets | Market Price [Member] |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MWh | [1] | (1) |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | FTRs [Member] | Commodity | Minimum | Assets | Market Price [Member] | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MWh | [1] | (1) |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | FTRs [Member] | Commodity | Maximum | Derivative Financial Instruments, Liabilities | Market Price [Member] |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MWh | [1] | 5 |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | FTRs [Member] | Commodity | Maximum | Derivative Financial Instruments, Liabilities | Market Price [Member] | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MWh | [1] | 5 |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | FTRs [Member] | Commodity | Maximum | Assets | Market Price [Member] |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MWh | [1] | 5 |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | FTRs [Member] | Commodity | Maximum | Assets | Market Price [Member] | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MWh | [1] | 5 |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | FTRs [Member] | Commodity | Weighted Average | Derivative Financial Instruments, Liabilities | Market Price [Member] |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MWh | [1],[2] | 0 |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | FTRs [Member] | Commodity | Weighted Average | Derivative Financial Instruments, Liabilities | Market Price [Member] | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MWh | [1],[2] | 0 |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | FTRs [Member] | Commodity | Weighted Average | Assets | Market Price [Member] |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MWh | [1],[2] | 1 |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | FTRs [Member] | Commodity | Weighted Average | Assets | Market Price [Member] | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MWh | [1],[2] | 1 |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | Natural Gas | Commodity |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Fair Value of Derivative Assets | [3] | $ 112 |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | Natural Gas | Commodity | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Fair Value of Derivative Assets | [3] | $ 112 |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | Natural Gas | Commodity | Minimum | Assets | Market Price [Member] |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MMBTU | [1] | (2) |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | Natural Gas | Commodity | Minimum | Assets | Market Price [Member] | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MMBTU | [1] | (2) |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | Natural Gas | Commodity | Maximum | Assets | Market Price [Member] |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MMBTU | [1] | 3 |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | Natural Gas | Commodity | Maximum | Assets | Market Price [Member] | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MMBTU | [1] | 2 |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | Natural Gas | Commodity | Weighted Average | Assets | Market Price [Member] |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MMBTU | [1],[2] | (1) |
Fair Value, Measurements, Recurring | Level 3 | Discounted Cash Flow [Member] | Natural Gas | Commodity | Weighted Average | Assets | Market Price [Member] | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MMBTU | [1],[2] | (1) |
Fair Value, Measurements, Recurring | Level 3 | Option Model [Member] | Natural Gas | Physical Options [Member] |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Fair Value of Derivative Liabilities |  | $ 2 |
Fair Value, Measurements, Recurring | Level 3 | Option Model [Member] | Natural Gas | Physical Options [Member] | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Fair Value of Derivative Liabilities |  | $ 2 |
Fair Value, Measurements, Recurring | Level 3 | Option Model [Member] | Natural Gas | Physical Options [Member] | Minimum | Derivative Financial Instruments, Liabilities | Market Price [Member] |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MMBTU | [1] | 1 |
Fair Value, Measurements, Recurring | Level 3 | Option Model [Member] | Natural Gas | Physical Options [Member] | Minimum | Derivative Financial Instruments, Liabilities | Market Price [Member] | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MMBTU | [1] | 1 |
Fair Value, Measurements, Recurring | Level 3 | Option Model [Member] | Natural Gas | Physical Options [Member] | Minimum | Derivative Financial Instruments, Liabilities | Price Volatility [Member] |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Price volatility (percentage) | [4] | 56.00% |
Fair Value, Measurements, Recurring | Level 3 | Option Model [Member] | Natural Gas | Physical Options [Member] | Minimum | Derivative Financial Instruments, Liabilities | Price Volatility [Member] | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Price volatility (percentage) | [4] | 56.00% |
Fair Value, Measurements, Recurring | Level 3 | Option Model [Member] | Natural Gas | Physical Options [Member] | Maximum | Derivative Financial Instruments, Liabilities | Market Price [Member] |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MMBTU | [1] | 5 |
Fair Value, Measurements, Recurring | Level 3 | Option Model [Member] | Natural Gas | Physical Options [Member] | Maximum | Derivative Financial Instruments, Liabilities | Market Price [Member] | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MMBTU | [1] | 5 |
Fair Value, Measurements, Recurring | Level 3 | Option Model [Member] | Natural Gas | Physical Options [Member] | Maximum | Derivative Financial Instruments, Liabilities | Price Volatility [Member] |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Price volatility (percentage) | [4] | 72.00% |
Fair Value, Measurements, Recurring | Level 3 | Option Model [Member] | Natural Gas | Physical Options [Member] | Maximum | Derivative Financial Instruments, Liabilities | Price Volatility [Member] | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Price volatility (percentage) | [4] | 72.00% |
Fair Value, Measurements, Recurring | Level 3 | Option Model [Member] | Natural Gas | Physical Options [Member] | Weighted Average | Derivative Financial Instruments, Liabilities | Market Price [Member] |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MMBTU | [1],[2] | 2 |
Fair Value, Measurements, Recurring | Level 3 | Option Model [Member] | Natural Gas | Physical Options [Member] | Weighted Average | Derivative Financial Instruments, Liabilities | Market Price [Member] | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Market Price | $ / MMBTU | [1],[2] | 2 |
Fair Value, Measurements, Recurring | Level 3 | Option Model [Member] | Natural Gas | Physical Options [Member] | Weighted Average | Derivative Financial Instruments, Liabilities | Price Volatility [Member] |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Price volatility (percentage) | [2],[4] | 66.00% |
Fair Value, Measurements, Recurring | Level 3 | Option Model [Member] | Natural Gas | Physical Options [Member] | Weighted Average | Derivative Financial Instruments, Liabilities | Price Volatility [Member] | Virginia Electric and Power Company |  |  |
Fair Value, Option, Quantitative Disclosures [Line Items] |  |  |
Price volatility (percentage) | [2],[4] | 66.00% |
[1] | Represents market prices beyond defined terms for Levels 1 and 2.
[2] | Averages weighted by volume.
[3] | Includes basis.
[4] | Represents volatilities unrepresented in published markets.

X
- Definition Fair value assumptions, expected volatility rate for commodity contracts. + References No definition available. + Details
Name: | d_FairValueAssumptionsExpectedVolatilityRateForCommodityContracts
Namespace Prefix: | d_
Data Type: | num:percentItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair value inputs, offered quotes for commodity contracts. + References No definition available. + Details
Name: | d_FairValueInputsOfferedQuotesForCommodityContracts
Namespace Prefix: | d_
Data Type: | srt-types:perUnitItemType
Balance Type: | na
Period Type: | duration

X
- Definition Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
Name: | us-gaap_AssetsFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
Name: | us-gaap_DerivativeAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value, after the effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=118260190&loc=d3e13433-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 + Details
Name: | us-gaap_DerivativeLiabilities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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

X
- Definition Fair value of financial and nonfinancial obligations. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
Name: | us-gaap_LiabilitiesFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

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

X
- Details
Name: | us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsRecurringMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_CommodityContractMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationTechniqueAxis=us-gaap_IncomeApproachValuationTechniqueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_EnergyAxis=d_FinancialTransmissionRightsMember
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_FairValueByLiabilityClassAxis=us-gaap_DerivativeFinancialInstrumentsLiabilitiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=d_MarketPriceMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=us-gaap_DerivativeFinancialInstrumentsAssetsMember
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_WeightedAverageMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | srt_ReserveQuantitiesByTypeOfReserveAxis=srt_NaturalGasReservesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_ValuationTechniqueAxis=us-gaap_MarketApproachValuationTechniqueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_CommodityOptionMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_MeasurementInputTypeAxis=d_PriceVolatilityMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |