Goodwill and Intangible Assets (Components of Intangible Assets) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 870	$ 864
Accumulated Amortization	310	328
Virginia Electric and Power Company
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	271	303
Accumulated Amortization	78	122
Software, licenses and other
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	867	859
Accumulated Amortization	308	327
Software, licenses and other | Virginia Electric and Power Company
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	271	303
Accumulated Amortization	78	122
Emissions allowances
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	3	5
Accumulated Amortization	$ 2	$ 1