Operating Revenue (Schedule of Operating Revenue) (Details) - USD ($) $ in Millions		3 Months Ended		9 Months Ended
		Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Electric sales:
Regulated		$ 2,108	$ 2,147	$ 5,590	$ 5,707
Nonregulated		380	399	1,114	1,123
Gas sales:
Regulated		97	46	696	137
Nonregulated		69	87	323	259
Gas transportation and storage		406	378	1,328	1,162
Other		119	75	325	263
Total operating revenue		3,179	3,132	9,376	8,651
Virginia Electric and Power Company
Electric sales:
Regulated		2,108	2,147	5,590	5,707
Gas sales:
Other		46	64	142	170
Total operating revenue	[1]	2,154	2,211	5,732	5,877
Dominion Energy Gas Holdings, LLC
Gas sales:
Regulated		12	28	59	69
Nonregulated		2	1	12	8
Gas transportation and storage		324	303	1,062	955
Other		63	50	180	149
Total operating revenue	[2]	$ 401	$ 382	$ 1,313	$ 1,181

[1] See Note 17 for amounts attributable to affiliates.

[2] See Note 17 for amounts attributable to related parties.