Employee Benefit Plans (Narrative) (Details)	3 Months Ended
	Mar. 31, 2016 USD ($)
Defined Benefit Plan Disclosure [Line Items]
Contributions to defined benefit pension plans and OPEB plans	$ 0
Expected contribution to voluntary employees' beneficiary association	12,000,000
Dominion Gas Holdings, LLC
Defined Benefit Plan Disclosure [Line Items]
Contributions to defined benefit pension plans and OPEB plans	0
Expected contribution to voluntary employees' beneficiary association	12,000,000
Special Termination Benefits | Organizational Design Initiative
Defined Benefit Plan Disclosure [Line Items]
Organizational design initiative	70,000,000
Organizational design initiative, after tax	43,000,000
Special Termination Benefits | Organizational Design Initiative | Virginia Electric and Power Company
Defined Benefit Plan Disclosure [Line Items]
Organizational design initiative	40,000,000
Organizational design initiative, after tax	25,000,000
Special Termination Benefits | Organizational Design Initiative | Dominion Gas Holdings, LLC
Defined Benefit Plan Disclosure [Line Items]
Organizational design initiative	8,000,000
Organizational design initiative, after tax	$ 5,000,000