Variable Interest Entities (Narrative) (Details) (USD $) In Millions, unless otherwise specified	9 Months Ended		1 Months Ended		3 Months Ended		9 Months Ended				3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Aug. 31, 2013 Juniper	Sep. 30, 2014 Variable Interest Entity, Not Primary Beneficiary Atlantic Coast Pipeline Jointly Owned Natural Gas Pipeline Pipelines Gas Distribution	Sep. 30, 2014 Virginia Electric and Power Company	Sep. 30, 2013 Virginia Electric and Power Company	Sep. 30, 2014 Virginia Electric and Power Company generator MW	Sep. 30, 2013 Virginia Electric and Power Company	Sep. 30, 2014 Virginia Electric and Power Company Minimum	Sep. 30, 2014 Virginia Electric and Power Company Maximum	Sep. 30, 2014 Dominion Gas Holdings, LLC	Sep. 30, 2013 Dominion Gas Holdings, LLC	Sep. 30, 2014 Dominion Gas Holdings, LLC	Sep. 30, 2013 Dominion Gas Holdings, LLC
Variable Interest Entities [Line Items]
Acquisition of Juniper noncontrolling interest	$ 0	$ 923	$ 923
Initial membership interest percentage				45.00%
Long term capacity contract non utility generators (generators)							4
Aggregate generation capacity from long-term power and capacity contracts (MW)							870
Contracts expiry date start range									2015	2021
Remaining purchase commitments							752
Payment for electric capacity					55	53	166	161
Payment for electric energy					28	29	115	74
Shared services purchased					$ 82	$ 88	$ 246	$ 248			$ 27	$ 30	$ 78	$ 81