Significant Accounting Policies (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accounting Policy [Line Items]
Accrued unbilled revenue	$ 564	$ 555
Percentage of fuel currently subject to deferred fuel accounting	84.00%
Accounts payable for checks outstanding	42	38
Margin assets	287	620
Margin liabilities	34	2
Capitalized interest costs	80	66	91
Virginia Electric and Power Company
Accounting Policy [Line Items]
Accrued unbilled revenue	407	395
Income tax receivable	225
Noncurrent income tax payable	38	28
Income tax payable		22
Accounts payable for checks outstanding	20	21
Margin assets	6	11
Capitalized interest costs	39	33	31
AFUDC related to projects	8	32	37
Dominion Gas Holdings, LLC
Accounting Policy [Line Items]
Accrued unbilled revenue	127	106
Accounts payable for checks outstanding	9	7
Capitalized interest costs	1	5	23
Inventory under LIFO method	12	7
Amount exceeded on LIFO basis	98	77
State | Virginia Electric and Power Company
Accounting Policy [Line Items]
Income tax receivable		3
Noncurrent income taxes receivable	13	12
State | Dominion Gas Holdings, LLC
Accounting Policy [Line Items]
Noncurrent income taxes receivable	20	20
Noncurrent income tax payable	7	7
Income taxes payable	14	23
Income Taxes Receivable, Current		1
Federal | Dominion Gas Holdings, LLC
Accounting Policy [Line Items]
Income tax receivable	96
Income taxes payable		$ 17