Property, Plant and Equipment (Property, Plant and Equipment) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015
Utility:
Generation	$ 17,147	$ 15,656
Transmission	14,315	11,461
Distribution	16,381	13,128
Storage	2,814	2,460
Nuclear fuel	1,537	1,464
Gas gathering and processing	216	799
Oil and gas	1,652	0
General and other	1,450	927
Plant under construction	6,254	5,550
Total utility	61,766	51,445
Nonutility:
Merchant generation-nuclear	1,419	1,339
Merchant generation-other	4,149	2,683
Nuclear fuel	897	938
Other-including plant under construction	706	1,371
Total nonutility	7,790	6,331
Total property, plant and equipment	69,556	57,776
Gas gathering and processing
Nonutility:
Total property, plant and equipment	619	0
Virginia Electric and Power Company
Utility:
Generation	17,147	15,656
Transmission	7,871	6,963
Distribution	10,573	10,048
Nuclear fuel	1,537	1,464
General and other	745	709
Plant under construction	2,146	2,793
Total utility	40,019	37,633
Nonutility:
Total nonutility	11	6
Total property, plant and equipment	40,030	37,639
Dominion Gas Holdings, LLC
Utility:
Transmission	4,231	3,804
Distribution	3,019	2,765
Storage	1,627	1,583
Gas gathering and processing	198	797
General and other	184	165
Plant under construction	448	443
Total utility	9,707	9,557
Nonutility:
Other-including plant under construction	149	136
Total nonutility	768	136
Total property, plant and equipment	10,475	9,693
Dominion Gas Holdings, LLC | Gas gathering and processing
Nonutility:
Total property, plant and equipment	$ 619	$ 0