Property, Plant and Equipment (Property, Plant and Equipment) (Detail) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Utility:
Generation	$ 25,317	$ 18,896
Transmission	20,486	16,666
Distribution	25,748	18,535
Storage	3,227	2,906
Nuclear fuel	2,296	1,626
Oil and gas	1,792	1,763
General and other	2,413	1,783
Plant under construction	2,956	2,348
Total utility	84,235	64,523
Non-jurisdictional—including plant under construction	854	407
Nonutility:
Merchant generation-nuclear	1,652	1,550
Merchant generation-other	3,985	3,802
Nuclear fuel	930	1,025
Gas gathering and processing	190	185
LNG facility	4,425	3,977
Other-including plant under construction	1,195	1,109
Total nonutility	12,377	11,648
Total property, plant and equipment	97,466	76,578
Virginia Electric and Power Company
Utility:
Generation	19,552	18,896
Transmission	10,229	9,391
Distribution	12,095	11,771
Nuclear fuel	1,688	1,626
General and other	825	820
Plant under construction	1,784	1,602
Total utility	46,173	44,106
Non-jurisdictional—including plant under construction	854	407
Nonutility:
Other-including plant under construction	11	11
Total property, plant and equipment	47,038	44,524
Dominion Energy Gas Holdings, LLC
Utility:
Transmission	7,014	6,790
Storage	2,799	2,615
General and other	219	210
Plant under construction	574	732
Total utility	10,606	10,347
Nonutility:
LNG facility	4,425	3,977
Other-including plant under construction	135	376
Total nonutility	4,560	4,353
Total property, plant and equipment	$ 15,166	$ 14,700