This item represents the entity's aggregate generation capacity from long-term power and capacity contracts.

No definition available.

Name:	d_AggregateGenerationCapacityFromLongTermPowerAndCapacityContractsMw
Namespace Prefix:	d_
Data Type:	xbrli:decimalItemType
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Period Type:	duration

- Definition

Costs incurred in purchasing electric capacity.

+ References

No definition available.

+ Details

Name:	d_CostPurchasedElectricCapacity
Namespace Prefix:	d_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Long Term Capacity Contract Non Utility Generators

+ References

No definition available.

+ Details

Name:	d_LongTermCapacityContractNonUtilityGenerators
Namespace Prefix:	d_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Definition

Long Term Power and Capacity Contract Expiration Date

+ References

No definition available.

+ Details

Name:	d_LongTermPowerAndCapacityContractExpirationDate
Namespace Prefix:	d_
Data Type:	xbrli:gYearItemType
Balance Type:	na
Period Type:	duration

- Definition

Long-term Capacity Contract, Expired, Number of Non-utility Generators

+ References

No definition available.

+ Details

Name:	d_LongtermCapacityContractExpiredNumberofNonutilityGenerators
Namespace Prefix:	d_
Data Type:	xbrli:integerItemType
Balance Type:	na
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- Definition

Public Utilities, Length of Pipeline

+ References

No definition available.

+ Details

Name:	d_PublicUtilitiesLengthofPipeline
Namespace Prefix:	d_
Data Type:	num:lengthItemType
Balance Type:	na
Period Type:	duration

- Definition

Shared Services Purchased

+ References

No definition available.

+ Details

Name:	d_SharedServicesPurchased
Namespace Prefix:	d_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Variable Interest Entities [Line Items]

+ References

No definition available.

+ Details

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Namespace Prefix:	d_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Cost incurred in providing energy services during the reporting period.

+ 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(d))
-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

+ Details

Name:	us-gaap_CostOfServicesEnergyServices
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of units or percentage investment held by one or more members or limited partners of the LLC or LP.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 272
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The minimum amount the entity agreed to spend under the long-term purchase commitment.

+ References

No definition available.

+ Details

Name:	us-gaap_LongTermPurchaseCommitmentAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 810
-SubTopic 10
-Section 50
-Paragraph 5A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=52262685&loc=SL6759159-111685

+ Details

Name:	us-gaap_VariableInterestEntityOwnershipPercentage
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	dei_LegalEntityAxis=d_DominionMidstreamPartnersLPMember
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- Details

Name:	us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis=us-gaap_VariableInterestEntityPrimaryBeneficiaryMember
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Data Type:	na
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- Details

Name:	us-gaap_EquityInterestIssuedOrIssuableByTypeAxis=us-gaap_PartnershipInterestMember
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Data Type:	na
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- Details

Name:	us-gaap_CapitalizedCostsOfUnprovedPropertiesExcludedFromAmortizationByPropertyOrProjectAxis=d_MerchantSolarProjectsMember
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Data Type:	na
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- Details

Name:	us-gaap_VariableInterestEntitiesByClassificationOfEntityAxis=us-gaap_VariableInterestEntityNotPrimaryBeneficiaryMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	us-gaap_JointlyOwnedUtilityPlantAxis=d_JointlyOwnedNaturalGasPipelineMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=d_AtlanticCoastPipelineLLCMember
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Data Type:	na
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- Details

Name:	us-gaap_PropertyPlantAndEquipmentByTypeAxis=us-gaap_PipelinesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_PublicUtilityAxis=us-gaap_GasDistributionMember
Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

Name:	dei_LegalEntityAxis=d_VirginiaElectricAndPowerCompanyMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_RangeAxis=us-gaap_MinimumMember
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Data Type:	na
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- Details

Name:	us-gaap_RangeAxis=us-gaap_MaximumMember
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Data Type:	na
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- Details

Name:	dei_LegalEntityAxis=d_DominionGasHoldingsLLCMember
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Variable Interest Entities (Narrative) (Details) $ in Millions	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2016 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2016 USD ($) MW generator mi	Sep. 30, 2015 USD ($)	Dec. 31, 2015 generator
Dominion Midstream Partners, LP
Variable Interest Entities [Line Items]
Ownership interest percentage of limited partner interests			65.00%
Variable Interest Entity, Primary Beneficiary \| Partnership Interest \| Merchant Solar Projects
Variable Interest Entities [Line Items]
Ownership percentage			67.00%
Variable Interest Entity, Primary Beneficiary \| Dominion Midstream Partners, LP \| Partnership Interest
Variable Interest Entities [Line Items]
Ownership interest percentage of limited partner interests			65.00%
Variable Interest Entity, Not Primary Beneficiary \| Jointly Owned Natural Gas Pipeline \| Atlantic Coast Pipeline \| Pipelines \| Gas Distribution
Variable Interest Entities [Line Items]
Ownership percentage			48.00%
Length of natural gas pipeline (in miles) \| mi			600
Variable Interest Entity, Not Primary Beneficiary \| Virginia Electric and Power Company
Variable Interest Entities [Line Items]
Long term capacity contract non utility generators (generators) \| generator			3		5
Number of expired non-utility generators \| generator					2
Aggregate generation capacity from long-term power and capacity contracts (MW) \| MW			418
Remaining purchase commitments			$ 320
Payment for electric capacity	$ 37	$ 52	111	$ 160
Payment for electric energy	11	17	23	77
Shared services purchased	80	73	$ 268	239
Variable Interest Entity, Not Primary Beneficiary \| Virginia Electric and Power Company \| Minimum
Variable Interest Entities [Line Items]
Contracts expiry date start range			2017
Variable Interest Entity, Not Primary Beneficiary \| Virginia Electric and Power Company \| Maximum
Variable Interest Entities [Line Items]
Contracts expiry date start range			2021
Variable Interest Entity, Not Primary Beneficiary \| Dominion Gas Holdings, LLC
Variable Interest Entities [Line Items]
Shared services purchased	$ 31	$ 27	$ 95	$ 85