Derivatives and Hedge Accounting Activities (Selected Information Related to Gains (Losses) on Cash Flow Hedges Included in AOCI) (Details) $ in Millions	6 Months Ended
Jun. 30, 2016 USD ($)
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	$ (241)
Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax	47
Commodity \| Gas Energy Contract
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	10
Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax	$ 9
Maximum Term	22 months
Commodity \| Electricity Energy Contract
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	$ 65
Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax	$ 65
Maximum Term	18 months
Commodity \| Other Energy Contract
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	$ (1)
Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax	$ (1)
Maximum Term	9 months
Interest rate
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	$ (312)
Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax	$ (23)
Maximum Term	381 months
Foreign currency
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	$ (3)
Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax	$ (3)
Maximum Term	120 months
Virginia Electric and Power Company
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	$ (21)
Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax	(1)
Virginia Electric and Power Company \| Interest rate
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	(21)
Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax	$ (1)
Maximum Term	381 months
Dominion Gas Holdings, LLC
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	$ (34)
Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax	(8)
Dominion Gas Holdings, LLC \| Commodity \| NGLs
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	(1)
Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax	$ (1)
Maximum Term	9 months
Dominion Gas Holdings, LLC \| Interest rate \| NGLs
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	$ (30)
Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax	$ (4)
Maximum Term	342 months
Dominion Gas Holdings, LLC \| Foreign currency
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	$ (3)
Amounts Expected to be Reclassified to Earnings During the Next 12 Months After-Tax	$ (3)
Maximum Term	120 months

Accumulated change, net of tax, in accumulated gains and losses from instruments designated and qualifying as the effective portion of cash flow hedges that will be reclassified into earnings during the next 12 months.

No definition available.

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- Definition

Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669646-108580

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
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-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669686-108580

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
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-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e681-108580

Reference 5: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=35736893&loc=d3e80784-113994

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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.

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Maximum length of time over which the entity is hedging its exposure to the variability in future cash flows for forecasted transactions, excluding those forecasted transactions related to the payment of variable interest on existing financial instruments, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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-Name Accounting Standards Codification
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