Credit Risk	12 Months Ended
Credit Risk	Dec. 31, 2019
Risks and Uncertainties [Abstract]
Credit Risk	Note 24. Credit Risk Dominion Energy As a diversified energy company, Dominion Energy transacts primarily with major companies in the energy industry and with commercial and residential energy consumers. These transactions principally occur in the Northeast, mid-Atlantic, Midwest and Rocky Mountain and Southeast regions of the U.S. Dominion Energy does not believe that this geographic concentration contributes significantly to its overall exposure to credit risk. In addition, as a result of its large and diverse customer base, Dominion Energy is not exposed to a significant concentration of credit risk for receivables arising from electric and gas utility operations. Dominion Energy’s exposure to credit risk is concentrated primarily within its energy marketing and price risk management activities, as Dominion Energy transacts with a smaller, less diverse group of counterparties and transactions may involve large notional volumes and potentially volatile commodity prices. Energy marketing and price risk management activities include marketing of merchant generation output, structured transactions and the use of financial contracts for enterprise-wide hedging purposes. Gross credit exposure for each counterparty is calculated as outstanding receivables plus any unrealized on- or off-balance sheet exposure, taking into account contractual netting rights. Gross credit exposure is calculated prior to the application of any collateral. At December 31, 2019, Dominion Energy’s credit exposure totaled $233 million. Of this amount, investment grade counterparties, including those internally rated, represented 88%, and no single counterparty, whether investment grade or non-investment grade, exceeded $61 million of exposure. Virginia Power Virginia Power sells electricity and provides distribution and transmission services to customers in Virginia and northeastern North Carolina. Management believes that this geographic concentration risk is mitigated by the diversity of Virginia Power’s customer base, which includes residential, commercial and industrial customers, as well as rural electric cooperatives and municipalities. Credit risk associated with trade accounts receivable from energy consumers is limited due to the large number of customers. Virginia Power’s exposure to potential concentrations of credit risk results primarily from sales to wholesale customers. Virginia Power’s gross credit exposure for each counterparty is calculated as outstanding receivables plus any unrealized on- or off-balance sheet exposure, taking into account contractual netting rights. Gross credit exposure is calculated prior to the application of collateral. At December 31, 2019, Virginia Power’s credit exposure totaled $71 million. Of this amount, investment grade counterparties, including those internally rated, represented 96%, and no single counterparty exceeded $61 million of exposure. Dominion Energy Gas Dominion Energy Gas transacts mainly with major companies in the energy industry. These transactions principally occur in the eastern and Rocky Mountain regions of the U.S. Dominion Energy Gas does not believe that this geographic concentration contributes to its overall exposure to credit risk. In addition, as a result of its large and diverse customer base, Dominion Energy Gas is not exposed to a significant concentration of credit risk for receivables arising from its regulated operations. Dominion Energy Gas’ gross credit exposure for each counterparty is calculated as outstanding receivables plus any unrealized on- or off-balance sheet exposure, taking into account contractual netting rights. Gross credit exposure is calculated prior to the application of collateral. At December 31, 2019, Dominion Energy Gas’ credit exposure totaled $46 million. Of this amount, investment grade counterparties, including those internally rated, represented 81%, and no single counterparty, whether investment grade or non-investment grade, exceeded $9 million of exposure. Upon the Liquefaction Facility commencing commercial operations in April 2018, the majority of Cove Point’s revenue and earnings are expected to be generated from annual reservation payments under certain terminalling, storage and transportation contracts with the Export Customers. If such agreements were terminated and Cove Point was unable to replace such agreements on comparable terms, there could be a material impact on results of operations, financial condition and/or cash flows. The Export Customers comprised approximately 34% and 32% of Dominion Energy Gas’ operating revenues for the years ended December 31, 2019 and 2018, respectively, with Dominion Energy Gas’ largest customer representing approximately 17% and 12% of such amounts. In 2019, DETI provided service to 296 customers with approximately 98% of its storage and transportation revenue being provided through firm services. The ten largest customers provided approximately 38% of the total storage and transportation revenue and the thirty largest provided approximately 72% of the total storage and transportation revenue. Credit-Related Contingent Provisions The majority of Dominion Energy’s derivative instruments contain credit-related contingent provisions. These provisions require Dominion Energy to provide collateral upon the occurrence of specific events, primarily a credit rating downgrade. If the credit-related contingent features underlying these instruments that are in a liability position and not fully collateralized with cash were fully triggered as of December 31, 2019 and 2018, Dominion Energy would have been required to post an additional $10 million and $1 million, respectively, of collateral to its counterparties. The collateral that would be required to be posted includes the impacts of any offsetting asset positions and any amounts already posted for derivatives, non-derivative contracts and derivatives elected under the normal purchases and normal sales exception, per contractual terms. Dominion Energy had posted no collateral at December 31, 2019 and 2018, related to derivatives with credit-related contingent provisions that are in a liability position and not fully collateralized with cash. The aggregate fair value of all derivative instruments with credit-related contingent provisions that are in a liability position and not fully collateralized with cash as of December 31, 2019 and 2018 was $10 million and $1 million, respectively, which does not include the impact of any offsetting asset positions. If the credit-related contingent features underlying these instruments that are in a liability position and not fully collateralized with cash were fully triggered as of December 31, 2019, Virginia Power would have been required to post an additional $8 million of collateral to its counterparties. Credit-related contingent provisions for Virginia Power were not material as of December 31, 2018. Credit-related contingent provisions for Dominion Energy Gas were not material as of December 31, 2019 and 2018. See Note 7 for further information about derivative instruments.