Fair Value Measurements (Financial Instruments' Carrying Amounts and Fair Values) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015		Dec. 31, 2014
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Junior subordinated notes	$ 1,373		$ 1,374	[1]
Valuation of certain fair value hedges	15		19
Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Long-term Debt	19,718	[2],[3]	19,723	[2],[3]
Junior subordinated notes	1,373	[3]	1,374	[3]
Remarketable subordinated notes	2,084	[3]	2,083	[3]
Estimate of Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Long-term Debt	22,197	[2],[3],[4]	21,881	[2],[3],[4]
Junior subordinated notes	1,405	[3],[4]	1,396	[3],[4]
Remarketable subordinated notes	2,206	[3],[4]	2,362	[3],[4]
Virginia Electric and Power Company | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Long-term Debt	8,936	[3]	8,937	[3]
Virginia Electric and Power Company | Estimate of Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Long-term Debt	10,441	[3],[4]	10,293	[3],[4]
Dominion Gas Holdings, LLC | Carrying Amount
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Long-term Debt	2,594	[3]	2,594	[3]
Dominion Gas Holdings, LLC | Estimate of Fair Value
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Total Long-term Debt	$ 2,720	[3],[4]	$ 2,672	[3],[4]

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

[2] At March 31, 2015 and December 31, 2014, includes the valuation of certain fair value hedges associated with fixed rate debt of approximately $15 million and $19 million, respectively.

[3] Carrying amount includes amounts which represent the unamortized discount and/or premium.

[4] Fair value is estimated using market prices, where available, and interest rates currently available for issuance of debt with similar terms and remaining maturities. All fair value measurements are classified as Level 2. The carrying amount of debt issues with short-term maturities and variable rates refinanced at current market rates is a reasonable estimate of their fair value.