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Employee Benefit Plans (Narrative) (Detail) | 3 Months Ended
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Mar. 31, 2018 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
Contributions to defined benefit pension plans and OPEB plans | $ 0
Expected contribution to voluntary employees' beneficiary association for the remainder of 2018 | 12,000,000
Dominion Energy Gas Holdings, LLC |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
Contributions to defined benefit pension plans and OPEB plans | 0
Expected contribution to voluntary employees' beneficiary association for the remainder of 2018 | $ 12,000,000

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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 + Details
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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. + Details
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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 + Details
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- Details
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