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		Jun. 30, 2015	Dec. 31, 2014
Investment Holdings [Line Items]
Amortized Cost, Total		$ 2,867	$ 2,794
Total Unrealized Gains	[1]	1,349	1,408
Total Unrealized Losses	[1],[2]	(8)	(6)
Fair Value		4,208	4,196	[3]
Net assets related to pending sales and purchases of securities		8	3
Fair value of securities in an unrealized loss position		500	379
Cost method investments
Investment Holdings [Line Items]
Amortized Cost, Other Investments		74	86
Total Unrealized Gains	[1]	0	0
Total Unrealized Losses	[1]	0	0
Fair Value		74	86
Cash equivalents and other
Investment Holdings [Line Items]
Amortized Cost, Other Investments	[4]	15	16
Total Unrealized Gains	[1],[4]	0	0
Total Unrealized Losses	[1],[4]	0	0
Fair Value	[4]	15	16
Equity securities | U.S. large cap | U.S.:
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities		1,291	1,273
Total Unrealized Gains	[1]	1,310	1,353
Total Unrealized Losses	[1]	0	0
Fair Value		2,601	2,626
Corporate bonds
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities		455	424
Total Unrealized Gains	[1]	13	19
Total Unrealized Losses	[1]	(4)	(2)
Fair Value		464	441
U.S. Treasury securities and agency debentures
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities		569	597
Total Unrealized Gains	[1]	10	13
Total Unrealized Losses	[1]	(2)	(4)
Fair Value		577	606
State and municipal
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities		355	332
Total Unrealized Gains	[1]	16	23
Total Unrealized Losses	[1]	(2)	0
Fair Value		369	355
Other
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities		108	66
Total Unrealized Gains	[1]	0	0
Total Unrealized Losses	[1]	0	0
Fair Value		108	66
Virginia Electric and Power Company
Investment Holdings [Line Items]
Amortized Cost, Total		1,353	1,314
Total Unrealized Gains	[5]	600	619
Total Unrealized Losses	[5],[6]	(5)	(3)
Fair Value		1,948	1,930	[7]
Net assets related to pending sales and purchases of securities		6	6
Fair value of securities in an unrealized loss position		254	170
Virginia Electric and Power Company | Cost method investments
Investment Holdings [Line Items]
Amortized Cost, Other Investments		74	86
Total Unrealized Gains	[5]	0	0
Total Unrealized Losses	[5]	0	0
Fair Value		74	86
Virginia Electric and Power Company | Cash equivalents and other
Investment Holdings [Line Items]
Amortized Cost, Other Investments	[8]	6	6
Total Unrealized Gains	[5],[8]	0	0
Total Unrealized Losses	[5],[8]	0	0
Fair Value	[8]	6	6
Virginia Electric and Power Company | Equity securities | U.S. large cap | U.S.:
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities		586	563
Total Unrealized Gains	[5]	583	594
Total Unrealized Losses	[5]	0	0
Fair Value		1,169	1,157
Virginia Electric and Power Company | Corporate bonds
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities		252	242
Total Unrealized Gains	[5]	6	9
Total Unrealized Losses	[5]	(3)	(1)
Fair Value		255	250
Virginia Electric and Power Company | U.S. Treasury securities and agency debentures
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities		199	197
Total Unrealized Gains	[5]	2	3
Total Unrealized Losses	[5]	(1)	(2)
Fair Value		200	198
Virginia Electric and Power Company | State and municipal
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities		208	197
Total Unrealized Gains	[5]	9	13
Total Unrealized Losses	[5]	(1)	0
Fair Value		216	210
Virginia Electric and Power Company | Other
Investment Holdings [Line Items]
Amortized Cost, Marketable Securities		28	23
Total Unrealized Gains	[5]	0	0
Total Unrealized Losses	[5]	0	0
Fair Value		$ 28	$ 23

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

[2] The fair value of securities in an unrealized loss position was $500 million and $379 million at June 30, 2015 and December 31, 2014, respectively.

[3] Dominion’s Consolidated Balance Sheet at December 31, 2014 has been derived from the audited Consolidated Financial Statements at that date.

[4] Includes pending sales of securities of $8 million and $3 million at June 30, 2015 and December 31, 2014, respectively.

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

[6] The fair value of securities in an unrealized loss position was $254 million and $170 million at June 30, 2015 and December 31, 2014, respectively.

[7] Virginia Power’s Consolidated Balance Sheet at December 31, 2014 has been derived from the audited Consolidated Financial Statements at that date.

[8] Includes pending sales of securities of $6 million at both June 30, 2015 and December 31, 2014.