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Derivatives and Hedge Accounting Activities (Volume of Derivative Activity) (Parenthetical) (Detail) - Foreign currency | Sep. 30, 2019 EUR (€)
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Derivative [Line Items] |
Interest rate / Foreign currency (US Dollars, Euros) | € 250,000,000
Dominion Energy Gas Holdings, LLC |
Derivative [Line Items] |
Interest rate / Foreign currency (US Dollars, Euros) | € 250,000,000

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- Definition Nominal or face amount used to calculate payment on derivative. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1B -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5580258-113959 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 1A -Subparagraph (d) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5579245-113959 + Details
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