Significant Financing Transactions - (Commercial Paper, Bank Loans and Letters of Credit Outstanding) (Details) (USD $)	Mar. 31, 2015		Jul. 31, 2014		Jul. 01, 2014		Dec. 31, 2014
Line of Credit Facility [Line Items]
Facility Limit	$ 4,500,000,000
Outstanding Commercial Paper	3,200,000,000
Outstanding Letters of Credit	48,000,000
Facility Capacity Available	1,252,000,000
Virginia Electric and Power Company
Line of Credit Facility [Line Items]
Facility Limit	1,750,000,000
Outstanding Commercial Paper	1,588,000,000
Outstanding Letters of Credit	0
Facility Capacity Available	162,000,000
Dominion Gas Holdings, LLC
Line of Credit Facility [Line Items]
Facility Limit	500,000,000
Outstanding Commercial Paper	280,000,000
Outstanding Letters of Credit	0
Facility Capacity Available	220,000,000
Credit Facility 4 Billion
Line of Credit Facility [Line Items]
Facility Limit	4,000,000,000	[1]
Outstanding Commercial Paper	3,112,000,000	[1]
Outstanding Letters of Credit	0	[1]
Facility Capacity Available	888,000,000	[1]
Credit Facility, to support letters of credit	1,500,000,000.0
Credit Facility 4 Billion | Virginia Electric and Power Company
Line of Credit Facility [Line Items]
Facility Limit	1,500,000,000	[2]	1,500,000,000.0	[1]	1,250,000,000.00	[1]
Outstanding Commercial Paper	1,500,000,000	[2]
Outstanding Letters of Credit	0	[2]
Facility Capacity Available	0	[2]
Credit Facility, to support letters of credit	1,500,000,000.0
Credit Facility 4 Billion | Dominion Gas Holdings, LLC
Line of Credit Facility [Line Items]
Facility Limit	500,000,000	[3]					1,000,000,000	[1]
Outstanding Commercial Paper	280,000,000	[3]
Outstanding Letters of Credit	0	[3]
Facility Capacity Available	220,000,000	[3]
Credit Facility, to support letters of credit	1,500,000,000.0
Credit Facility 500 Million
Line of Credit Facility [Line Items]
Facility Limit	500,000,000	[4]
Outstanding Commercial Paper	88,000,000	[4]
Outstanding Letters of Credit	48,000,000	[4]
Facility Capacity Available	364,000,000	[4]
Credit Facility 500 Million | Virginia Electric and Power Company
Line of Credit Facility [Line Items]
Facility Limit	250,000,000	[5]
Outstanding Commercial Paper	88,000,000	[5]
Outstanding Letters of Credit	0	[5]
Facility Capacity Available	162,000,000	[5]
Credit Facility 500 Million | Dominion Gas Holdings, LLC
Line of Credit Facility [Line Items]
Facility Limit	0	[6]
Outstanding Commercial Paper	0	[6]
Outstanding Letters of Credit	0	[6]
Facility Capacity Available	$ 0	[6]

[1] This credit facility has a maturity date of April 2019, and can be used to support bank borrowings and the issuance of commercial paper, as well as to support up to $1.5 billion of letters of credit.

[2] This credit facility has a maturity date of April 2019, and can be used to support bank borrowings and the issuance of commercial paper, as well as to support up to $1.5 billion (or the sub-limit, whichever is less) of letters of credit. Virginia Power's current sub-limit under this credit facility can be increased or decreased multiple times per year. In January 2015, Virginia Power increased its sub-limit from $1.25 billion to $1.50 billion.

[3] This credit facility has a maturity date of April 2019, and can be used to support bank borrowings and the issuance of commercial paper, as well as to support up to $1.5 billion (or the sub-limit, whichever is less) of letters of credit. Dominion Gas' current sub-limit under this credit facility can be increased or decreased multiple times per year, up to a maximum of $1.0 billion.

[4] This credit facility has a maturity date of April 2019, and can be used to support bank borrowings, commercial paper and letter of credit issuances.

[5] This credit facility has a maturity date of April 2019, and can be used to support bank borrowings, commercial paper and letter of credit issuances. Virginia Power's current sub-limit under this credit facility can be increased or decreased multiple times per year.

[6] This credit facility has a maturity date of April 2019, and can be used to support bank borrowings, commercial paper and letter of credit issuances. Dominion Gas' current sub-limit under this credit facility can be increased or decreased multiple times per year.