Related Party Transactions (Details) - USD ($)		3 Months Ended		6 Months Ended
		Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Other deferred credits and other liabilities
Related Party Transaction [Line Items]
Amounts due to Dominion		$ 268,000,000		$ 268,000,000		$ 219,000,000
Other deferred charges and other assets
Related Party Transaction [Line Items]
Amounts due from Dominion		56,000,000		56,000,000
Virginia Electric and Power Company
Related Party Transaction [Line Items]
Commodity purchases from affiliates		94,000,000	$ 113,000,000	346,000,000	$ 315,000,000
Services provided to affiliates	[1]	107,000,000	106,000,000	217,000,000	214,000,000
Sales of natural gas and transportation and storage services to affiliates		5,000,000	6,000,000	10,000,000	11,000,000
Outstanding borrowings, net of repayments, under money pool for non-regulated subsidiaries		0		0		0
Virginia Electric and Power Company | Principal Owner
Related Party Transaction [Line Items]
Short term demand note		0		0		427,000,000
Dominion Gas Holdings, LLC
Related Party Transaction [Line Items]
Amounts due from Dominion	[2]	2,000,000		2,000,000		3,000,000
Commodity purchases from affiliates		2,000,000	6,000,000	4,000,000	8,000,000
Services provided to affiliates		25,000,000	10,000,000	45,000,000	22,000,000
Sales of natural gas and transportation and storage services to affiliates		17,000,000	21,000,000	35,000,000	46,000,000
Other receivables	[3]	6,000,000		6,000,000		17,000,000
Customer receivables from related parties		9,000,000		9,000,000		5,000,000
Affiliated notes receivable	[4]	12,000,000		12,000,000		9,000,000
Dominion Gas Holdings, LLC | Revolving Credit Facility | IRCA
Related Party Transaction [Line Items]
Borrowings under IRCA		168,000,000		168,000,000		$ 384,000,000
Dominion Gas Holdings, LLC | Services provided by affiliates
Related Party Transaction [Line Items]
Commodity purchases from affiliates	[1]	$ 35,000,000	$ 25,000,000	$ 69,000,000	$ 51,000,000

[1] Includes capitalized expenditures.

[2] Amounts are presented in other current assets in Dominion Gas' Consolidated Balance Sheets.

[3] Represents amounts due from Atlantic Coast Pipeline, a related party VIE.

[4] Amounts are presented in other deferred charges and other assets in Dominion Gas' Consolidated Balance Sheets.