Derivatives and Hedge Accounting Activities (Selected Information Related to Gains (Losses) on Cash Flow Hedges Included in AOCI) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	$ (178)	$ (288)
Amounts Expected to be Reclassified to Earnings during the next 12 Months After-Tax	33
Commodity | Electricity
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	56
Amounts Expected to be Reclassified to Earnings during the next 12 Months After-Tax	46
Maximum Term	24 months
Commodity | Gas
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	(8)
Amounts Expected to be Reclassified to Earnings during the next 12 Months After-Tax	(7)
Maximum Term	27 months
Commodity | Other
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	0
Amounts Expected to be Reclassified to Earnings during the next 12 Months After-Tax	0
Maximum Term	17 months
Interest rate
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	(226)
Amounts Expected to be Reclassified to Earnings during the next 12 Months After-Tax	(6)
Maximum Term	384 months
Dominion Gas Holdings, LLC
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	(20)	3
Amounts Expected to be Reclassified to Earnings during the next 12 Months After-Tax	0
Dominion Gas Holdings, LLC | Commodity | Natural Gas
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	0
Amounts Expected to be Reclassified to Earnings during the next 12 Months After-Tax	0
Maximum Term	3 months
Dominion Gas Holdings, LLC | Commodity | Other
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	0
Amounts Expected to be Reclassified to Earnings during the next 12 Months After-Tax	0
Maximum Term	12 months
Dominion Gas Holdings, LLC | Interest rate
Derivative Instruments, Gain (Loss) [Line Items]
AOCI After-Tax	(20)
Amounts Expected to be Reclassified to Earnings during the next 12 Months After-Tax	$ 0
Maximum Term	360 months