Property, Plant and Equipment (Property, Plant and Equipment) (Detail) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Utility:
Generation	$ 22,697	$ 25,317
Transmission	14,351	13,472
Distribution	27,311	25,746
Storage	436	428
Nuclear fuel	2,283	2,296
General and other	4,130	3,978
Plant under construction	3,350	2,377
Total utility	74,558	73,614
Non-jurisdictional - including plant under construction	1,225	854
Nonutility:
Nonregulated generation-nuclear	1,736	1,652
Nonregulated generation-other	3,268	3,985
Nuclear fuel	1,012	930
Other-including plant under construction	1,160	1,008
Total nonutility	7,176	7,575
Total property, plant and equipment	82,959	82,043
Virginia Electric and Power Company
Utility:
Generation	16,769	19,552
Transmission	11,000	10,229
Distribution	12,839	12,095
Nuclear fuel	1,709	1,688
General and other	845	825
Plant under construction	2,338	1,784
Total utility	45,500	46,173
Non-jurisdictional - including plant under construction	1,225	854
Nonutility:
Other-including plant under construction	11	11
Total property, plant and equipment	$ 46,736	$ 47,038