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.

No definition available.

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- Definition

Amount of realized and unrealized gain (loss) included in earnings, which have arisen from the use of significant unobservable inputs (level 3) to measure fair value of assets, liabilities, and financial instruments classified in shareholders' equity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Amount of increase (decrease) of financial instrument classified as a derivative asset (liability) after deduction of derivative liability (asset), measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19279-110258

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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Fair Value Measurements (Narrative) (Details) - USD ($)	3 Months Ended		9 Months Ended
Fair Value Measurements (Narrative) (Details) - USD ($)	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Virginia Electric and Power Company
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unrealized gains or losses included in earnings in Level 3 fair value category	$ 0	$ 0	$ 0	$ 0
Dominion Energy Gas Holdings, LLC
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Unrealized gains or losses included in earnings in Level 3 fair value category	0	0	$ 0	$ 0
Dominion Energy Gas Holdings, LLC \| Commodity contracts
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Net changes in assets and liabilities for derivatives measured at fair value on recurring basis	$ 0	$ 0