Shareholders' Equity (Summary of Changes in Amounts of Stock Options Outstanding) (Details) (USD $) In Millions, except Share data in Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012		Dec. 31, 2011		Dec. 31, 2010
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding [Roll Forward]
Outstanding and exercisable beginning, Shares	628		1,810		3,822
Exercised, Shares	(622)		(1,174)		(1,983)
Forfeited/expired, Shares	(6)		(8)		(29)
Outstanding and exercisable ending, Shares	0		628		1,810
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Weighted Average Exercise Price [Roll Forward]
Outstanding and exercisable beginning, Weighted-average Exercise Price	$ 30.81		$ 31.76		$ 31.25
Exercised, Weighted-average Exercise Price	$ 30.79		$ 32.46		$ 30.81
Forfeited/expired, Weighted-average Exercise Price	$ 32.26		$ 31.57		$ 29.84
Outstanding and exercisable ending, Weighted-average Exercise Price	$ 0.00		$ 30.81		$ 31.76
Outstanding and exercisable beginning, Weighted-average Remaining Contractual Life
Outstanding and exercisable ending, Weighted-average Remaining Contractual Life
Outstanding and exercisable beginning, Aggregated Intrinsic Value	$ 14	[1]	$ 20	[1]	$ 29	[1]
Exercised, Aggregated Intrinsic Value	13	[1]	17	[1]	22	[1]
Outstanding and exercisable ending, Aggregated Intrinsic Value	$ 0	[1]	$ 14	[1]	$ 20	[1]

[1] Intrinsic value represents the difference between the exercise price of the option and the market value of Dominion's stock.