Commitments and Contingencies (Nuclear Operations) (Narrative) (Details) (USD $)	1 Months Ended	12 Months Ended			1 Months Ended		1 Months Ended		12 Months Ended				3 Months Ended
	Oct. 31, 2008	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2011 Spent Nuclear Fuel	Oct. 31, 2008 Virginia Power [Member]	Dec. 31, 2011 Kewaunee Power Station Spent Nuclear Fuel	Oct. 31, 2008 Millstone Power Station	Dec. 31, 2011 Spent Nuclear Fuel	Dec. 31, 2011 Nuclear Plant [Member]	Dec. 31, 2011 Property Plant and Equipment [Member] Spent Nuclear Fuel	Dec. 31, 2011 Depreciaiton Expense [Member] Spent Nuclear Fuel	Dec. 31, 2011 Operations and Maintance Expense [Member] Spent Nuclear Fuel	Dec. 31, 2011 Surry And North Anna [Member] Spent Nuclear Fuel
Minimum financial assurance		$ 3,200,000,000
Liability protection under Price-Anderson Act									12,600,000,000
Amount of coverage purchased from commercial insurance pools		375,000,000
Amount that could be assessed for each licensed reactor		118,000,000
Amount that could be assessed for each licensed reactor per reactor		18,000,000
Coverage that exceeds NRC minimum requirement		1,060,000,000
Maximum assessment for premiums on insurance policy		78,000,000
Maximum assessment for insurance policy		31,000,000
Settlement payment						21,000,000
Receviables For Spent Nuclear Fuel Related Costs								102,000,000
Other receivables		255,000,000	88,000,000	64,000,000
Gain (Loss) Related to Litigation Settlement										24,000,000	17,000,000	7,000,000
Amount of litigation settlement	$ 155,000,000				$ 112,000,000		$ 43,000,000						$ 155,000,000