Property, Plant and Equipment (Property, Plant and Equipment) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2012		Dec. 31, 2011
Utility:
Generation	$ 13,707		$ 11,793
Transmission	7,799		6,604
Distribution	11,071		10,401
Storage	2,137		2,060
Nuclear fuel	1,277		1,193
Gas gathering and processing	803		727
General and other	803		778
Other-including plant under construction	2,232		3,597
Total utility	39,829		37,153
Nonutility:
Merchant generation-nuclear	1,163		1,108
Merchant generation-other	1,289	[1]	2,780	[1]
Nuclear fuel	775		847
Other-including plant under construction	1,265		1,102
Total nonutility	4,492		5,837
Total property, plant and equipment	44,321		42,990
Merchant generation other, due to consolidation of VIE	957
Virginia Electric and Power Company
Utility:
Generation	13,707		11,793
Transmission	4,261		3,823
Distribution	8,701		8,231
Nuclear fuel	1,277		1,193
General and other	659		631
Other-including plant under construction	2,017		2,946
Total utility	30,622		28,617
Nonutility:
Total nonutility	9		9
Total property, plant and equipment	$ 30,631		$ 28,626

[1] Amount includes $957 million due to consolidation of a VIE.