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	Sep. 30, 2014		Dec. 31, 2013
Investment Holdings [Line Items]
Amortized Cost, Total	$ 2,806		$ 2,669
Total Unrealized Gains	1,325	[1]	1,252	[1]
Total Unrealized Losses	(6)	[1],[2]	(18)	[1],[2]
Nuclear decommissioning trust funds	4,125		3,903	[3]
Net assets related to pending sales and purchases of securities	8		11
Fair Value of securities in an unrealized loss position	463		604
Cost method investments
Investment Holdings [Line Items]
Amortized Cost, Other Investments	86		106
Total Unrealized Gains	0	[1]	0	[1]
Total Unrealized Losses	0	[1]	0	[1]
Nuclear decommissioning trust funds	86		106
Cash Equivalents and Other Investment
Investment Holdings [Line Items]
Amortized Cost, Other Investments	135	[4]	110	[4]
Total Unrealized Gains	0	[1],[4]	0	[1],[4]
Total Unrealized Losses	0	[1],[4]	0	[1],[4]
Nuclear decommissioning trust funds	135	[4]	110	[4]
Equity Securities | U.S. Large cap | U.S.:
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities	1,252		1,183
Total Unrealized Gains	1,276	[1]	1,194	[1]
Total Unrealized Losses	0	[1]	0	[1]
Nuclear decommissioning trust funds	2,528		2,377
Equity Securities | Other | U.S.:
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities			49
Total Unrealized Gains			23	[1]
Total Unrealized Losses			0	[1]
Nuclear decommissioning trust funds			72
Corporate bonds
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities	402		332
Total Unrealized Gains	18	[1]	16	[1]
Total Unrealized Losses	(1)	[1]	(3)	[1]
Nuclear decommissioning trust funds	419		345
U.S. Treasury securities and agency debentures
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities	620		589
Total Unrealized Gains	9	[1]	8	[1]
Total Unrealized Losses	(5)	[1]	(10)	[1]
Nuclear decommissioning trust funds	624		587
State and municipal
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities	305		297
Total Unrealized Gains	22	[1]	11	[1]
Total Unrealized Losses	0	[1]	(5)	[1]
Nuclear decommissioning trust funds	327		303
Other
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities	6		3
Total Unrealized Gains	0	[1]	0	[1]
Total Unrealized Losses	0	[1]	0	[1]
Nuclear decommissioning trust funds	6		3
Virginia Electric and Power Company
Investment Holdings [Line Items]
Amortized Cost, Total	1,294		1,236
Total Unrealized Gains	580	[1]	538	[1]
Total Unrealized Losses	(2)	[1],[5]	(9)	[1],[5]
Nuclear decommissioning trust funds	1,872		1,765	[6]
Net assets related to pending sales and purchases of securities	2		6
Fair Value of securities in an unrealized loss position	201		299
Virginia Electric and Power Company | Cost method investments
Investment Holdings [Line Items]
Amortized Cost, Other Investments	86		106
Total Unrealized Gains	0	[1]	0	[1]
Total Unrealized Losses	0	[1]	0	[1]
Nuclear decommissioning trust funds	86		106
Virginia Electric and Power Company | Cash Equivalents and Other Investment
Investment Holdings [Line Items]
Amortized Cost, Other Investments	45	[7]	37	[7]
Total Unrealized Gains	0	[1],[7]	0	[1],[7]
Total Unrealized Losses	0	[1],[7]	0	[1],[7]
Nuclear decommissioning trust funds	45	[7]	37	[7]
Virginia Electric and Power Company | Equity Securities | U.S. Large cap | U.S.:
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities	543		506
Total Unrealized Gains	557	[1]	514	[1]
Total Unrealized Losses	0	[1]	0	[1]
Nuclear decommissioning trust funds	1,100		1,020
Virginia Electric and Power Company | Equity Securities | Other | U.S.:
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities			25
Total Unrealized Gains			11	[1]
Total Unrealized Losses			0	[1]
Nuclear decommissioning trust funds			36
Virginia Electric and Power Company | Corporate bonds
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities	221		185
Total Unrealized Gains	9	[1]	8	[1]
Total Unrealized Losses	(1)	[1]	(2)	[1]
Nuclear decommissioning trust funds	229		191
Virginia Electric and Power Company | U.S. Treasury securities and agency debentures
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities	226		214
Total Unrealized Gains	2	[1]	1	[1]
Total Unrealized Losses	(1)	[1]	(3)	[1]
Nuclear decommissioning trust funds	227		212
Virginia Electric and Power Company | State and municipal
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities	173		163
Total Unrealized Gains	12	[1]	4	[1]
Total Unrealized Losses	0	[1]	(4)	[1]
Nuclear decommissioning trust funds	$ 185		$ 163

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

[2] The fair value of securities in an unrealized loss position was $463 million and $604 million at September 30, 2014 and December 31, 2013, respectively.

[3] Dominion’s Consolidated Balance Sheet at December 31, 2013 has been derived from the audited Consolidated Financial Statements at that date.

[4] Includes pending sales of securities of $8 million and $11 million at September 30, 2014 and December 31, 2013, respectively.

[5] The fair value of securities in an unrealized loss position was $201 million and $299 million at September 30, 2014 and December 31, 2013, respectively.

[6] Virginia Power’s Consolidated Balance Sheet at December 31, 2013 has been derived from the audited Consolidated Financial Statements at that date.

[7] Includes pending sales of securities of $2 million and $6 million at September 30, 2014 and December 31, 2013