Investments (Recorded Other-Than-Temporary Impairment Losses on Investments) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Schedule of Available-for-sale Securities [Line Items]
Total other-than-temporary impairment losses	$ 31		$ 26		$ 75
Losses recorded to decommissioning trust regulatory liability	(13)		(10)		(24)
Losses recognized in other comprehensive income (before taxes)	10		2		3
Net impairment losses recognized in earnings	8		14		48
Other-than-temporary impairment losses for debt securities	18		4		6
Virginia Electric and Power Company
Schedule of Available-for-sale Securities [Line Items]
Total other-than-temporary impairment losses	15	[1]	11	[1]	29	[1]
Losses recorded to decommissioning trust regulatory liability	(13)		(10)		(24)
Losses recognized in other comprehensive income (before taxes)	1		0		1
Net impairment losses recognized in earnings	1		1		4
Other-than-temporary impairment losses for debt securities	$ 9		$ 2		$ 4

[1] Amounts include other-than-temporary impairment losses for debt securities of $9 million, $2 million and $4 million at December 31, 2013, 2012 and 2011, respectively.