Income Taxes (Unrecognized Tax Benefits) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at January 1	$ 293	$ 347	$ 307
Increases-prior period positions	17	28	127
Decreases-prior period positions	(99)	(106)	(119)
Increases-current period positions	30	43	64
Decreases-current period positions	(5)	0	(21)
Settlements with tax authorities	(2)	(4)	0
Expiration of statutes of limitations	(12)	(15)	(11)
Balance at December 31	222	293	347
Virginia Electric and Power Company
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Balance at January 1	57	114	117
Increases-prior period positions	12	4	22
Decreases-prior period positions	(42)	(80)	(51)
Increases-current period positions	14	24	47
Decreases-current period positions	0	0	(21)
Settlements with tax authorities	(2)	(4)	0
Expiration of statutes of limitations	0	(1)	0
Balance at December 31	$ 39	$ 57	$ 114