Investments (Marketable Equity and Debt Securities and Cash Equivalents (Classified as Available-for-sale) and Cost Method Investments in Decommissioning Trust Funds) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2012		Dec. 31, 2011
Amortized Cost, Total	$ 2,432		$ 2,390
Total Unrealized Gains	801	[1]	611	[1]
Total Unrealized Losses	(2)	[1],[2]	(2)	[1],[2]
Fair Value	3,231		2,999	[3]
Net assets related to pending sales and purchases of securities	20		11
Fair Value of securities in an unrealized loss position	192		164
Cost-method Investments [Member]
Amortized Cost, Other Investments	117		118
Total Unrealized Gains	0		0
Total Unrealized Losses	0		0
Fair Value	117		118
Cash Equivalents and Other Investment [Member]
Amortized Cost, Other Investments	58	[4]	46	[4]
Total Unrealized Gains	0		0
Total Unrealized Losses	0		0
Fair Value	58	[4]	46	[4]
Equity Securities [Member] | Large Cap | United States
Amortized Cost, Marketable Securities	1,178		1,152
Total Unrealized Gains	724	[1]	537	[1]
Total Unrealized Losses	0	[1]	0	[1]
Fair Value	1,902		1,689
Equity Securities [Member] | Other Market [Member] | United States
Amortized Cost, Marketable Securities	38		36
Total Unrealized Gains	15	[1]	10	[1]
Total Unrealized Losses	0	[1]	0	[1]
Fair Value	53		46
Corporate bonds
Amortized Cost, Marketable Securities	296		314
Total Unrealized Gains	22	[1]	19	[1]
Total Unrealized Losses	(1)	[1]	(1)	[1]
Fair Value	317		332
U.S. Treasury Securities and Agency Debentures
Amortized Cost, Marketable Securities	459		437
Total Unrealized Gains	18	[1]	20	[1]
Total Unrealized Losses	(1)	[1]	(1)	[1]
Fair Value	476		456
State and Municipal
Amortized Cost, Marketable Securities	267		264
Total Unrealized Gains	21	[1]	24	[1]
Total Unrealized Losses	0	[1]	0	[1]
Fair Value	288		288
Other Debt Securities
Amortized Cost, Marketable Securities	19		23
Total Unrealized Gains	1	[1]	1	[1]
Total Unrealized Losses	0	[1]	0	[1]
Fair Value	$ 20		$ 24

[1] Included in AOCI and the decommissioning trust regulatory liability.

[2] The fair value of securities in an unrealized loss position was $192 million and $164 million at March 31, 2012 and December 31, 2011, respectively.

[3] Dominion’s Consolidated Balance Sheet at December 31, 2011 has been derived from the audited Consolidated Financial Statements at that date.

[4] Includes pending purchases of securities of $20 million and $11 million at March 31, 2012 and December 31, 2011, respectively.