Defined benefit plan, net periodic benefit cost (credit), increase (decrease) for plan amendment, after tax.

No definition available.

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- Definition

Defined Benefit Plan, Plan Amendment, Retirement Age

+ References

No definition available.

+ Details

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- Definition

Restructuring charges, net of tax.

+ References

No definition available.

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- Definition

Amount of increase (decrease) in accumulated benefit obligation from change in existing term of defined benefit plan or initiation of new defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (r)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (k)(1)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- 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.

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- Definition

Amount of contributions expected to be received by defined benefit plan from employer in fiscal year. Excludes contributions paid by employer in current fiscal year.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 6
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2709-114920

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- Definition

Amount of increase (decrease) in net periodic benefit cost from effect of change in substantive term of existing defined benefit plan or initiation of new defined benefit plan.

+ References

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- Definition

The distributions of earnings to an entity that is affiliated with the reporting entity by means of direct or indirect ownership.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3291-108585

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- Definition

Amount of payment for pension and other postretirement benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3536-108585

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 5.P.3)
-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140864-122747

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
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-Section 45
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-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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-Name Accounting Standards Codification
-Topic 420
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-URI http://asc.fasb.org/extlink&oid=6394359&loc=d3e17939-110869

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-URI http://asc.fasb.org/extlink&oid=27011515&loc=d3e140904-122747

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Employee Benefit Plans (Narrative) (Details) - USD ($)	1 Months Ended	3 Months Ended	6 Months Ended
Employee Benefit Plans (Narrative) (Details) - USD ($)	Jan. 31, 2017	Mar. 31, 2017	Jun. 30, 2017	Jun. 30, 2016
Defined Benefit Plan Disclosure [Line Items]
Contributions to defined benefit pension plans and OPEB plans			$ 0
Expected contribution to voluntary employees' beneficiary association			12,000,000
Dominion Energy Questar Corporation \| Capital Contribution to Dominion Energy Questar to Fund Pension Contributions
Defined Benefit Plan Disclosure [Line Items]
Contribution to qualified pension plan	$ 75,000,000
Medical Coverage for Local 69 retirees
Defined Benefit Plan Disclosure [Line Items]
Retirement age		65 years
Decrease in accumulated postretirement benefit obligation		$ 73,000,000
Discount rate percentage		4.30%
Charge recorded from plan amendment and remeasurement			7,000,000
Charge recorded from plan amendment and remeasurement, after tax			4,000,000
Dominion Energy Gas Holdings, LLC
Defined Benefit Plan Disclosure [Line Items]
Contributions to defined benefit pension plans and OPEB plans			0
Contribution to qualified pension plan			15,000,000	$ 150,000,000
Expected contribution to voluntary employees' beneficiary association			12,000,000
Dominion Energy Gas Holdings, LLC \| Medical Coverage for Local 69 retirees
Defined Benefit Plan Disclosure [Line Items]
Decrease in accumulated postretirement benefit obligation		$ 61,000,000
Charge recorded from plan amendment and remeasurement			6,000,000
Charge recorded from plan amendment and remeasurement, after tax			$ 4,000,000
Special Termination Benefits \| Organizational Design Initiative
Defined Benefit Plan Disclosure [Line Items]
Organizational design initiative				65,000,000
Organizational design initiative, after tax				40,000,000
Special Termination Benefits \| Organizational Design Initiative \| Virginia Electric and Power Company
Defined Benefit Plan Disclosure [Line Items]
Organizational design initiative				33,000,000
Organizational design initiative, after tax				20,000,000
Special Termination Benefits \| Organizational Design Initiative \| Dominion Energy Gas Holdings, LLC
Defined Benefit Plan Disclosure [Line Items]
Organizational design initiative				8,000,000
Organizational design initiative, after tax				$ 5,000,000