Earnings Per Share (Calculation of Basic and Diluted EPS) (Details) - USD ($) $ / shares in Units, shares in Millions, $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Earnings Per Share [Abstract]
Net income attributable to Dominion Energy		$ 665	$ 690	$ 1,687	$ 1,666
Average shares of common stock outstanding – Basic		642.5	625.9	633.4	612.8
Net effect of dilutive securities	[1]	0.0	0.1	0.0	1.0
Average shares of common stock outstanding – Diluted		642.5	626.0	633.4	613.8
Earnings Per Common Share – Basic		$ 1.03	$ 1.10	$ 2.66	$ 2.72
Earnings Per Common Share – Diluted		$ 1.03	$ 1.10	$ 2.66	$ 2.71

[1] Dilutive securities consist primarily of the 2013 Equity Units for the nine months ended September 30, 2016. See Note 17 to the Consolidated Financial Statements in the Companies' Annual Report on Form 10-K for the year ended December 31, 2016 for more information.