Income Taxes (Reconciliation of Income Taxes at the U.S. Statutory Federal Rate as Compared to the Income Tax Expense Recorded in Our Consolidated Statements of Income) (Details)	9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013
Operating Loss Carryforwards [Line Items]
U.S. statutory rate	35.00%	35.00%
Increases (reductions) resulting from:
State taxes, net of federal benefit	2.70%	2.40%
Investment tax credits	(6.00%)	(1.30%)
Production tax credits	(1.10%)	(0.50%)
Valuation allowances	0.60%	0.00%
AFUDC - equity	0.10%	(0.70%)
Other, net	(0.60%)	(0.90%)
Effective tax rate	30.70%	34.00%
Virginia Electric and Power Company
Operating Loss Carryforwards [Line Items]
U.S. statutory rate	35.00%	35.00%
Increases (reductions) resulting from:
State taxes, net of federal benefit	3.90%	2.80%
Investment tax credits	0.00%	0.00%
Production tax credits	(0.60%)	(0.20%)
Valuation allowances	0.00%	0.00%
AFUDC - equity	0.10%	(1.10%)
Other, net	0.70%	(0.30%)
Effective tax rate	39.10%	36.20%
Dominion Gas Holdings, LLC
Operating Loss Carryforwards [Line Items]
U.S. statutory rate	35.00%	35.00%
Increases (reductions) resulting from:
State taxes, net of federal benefit	3.70%	4.10%
Investment tax credits	0.00%	0.00%
Production tax credits	0.00%	0.00%
Valuation allowances	0.00%	0.00%
AFUDC - equity	0.00%	(0.10%)
Other, net	0.10%	0.20%
Effective tax rate	38.80%	39.20%