Operating Segments (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
After-tax net expense	$ 2,593		$ 2,479	[1]
Income from discontinued operations	1		(10)	[1]
Corporate and Other
After-tax net expense	19		3
After tax net expenses attributable to operating segments	17
Income from discontinued operations	1	[2]	(10)	[2]
Dominion Generation
Net gain on investments	44		15
Net gain on invesments, after tax	26		9
Income from discontinued operations	0	[2]	0	[2]
Brayton Point and Kincaid | Dominion Generation
Benefit from discontinued operations	1
Net loss from discontinued operations, before income tax			22
Income from discontinued operations			11
Merchant Power Stations | Dominion Generation
Benefit from discontinued operations	38
Benefit from discontinued operations, net of tax	23
Impairment of long-lived assets to be disposed of	37
Impairment of long lived assets to be disposed of, net of tax	$ 22

[1] Recast to reflect Brayton Point and Kincaid as discontinued operations, as discussed in Note 3.

[2] 2012 amounts have been recast to reflect Brayton Point and Kincaid as discontinued operations, as discussed in Note 3.