Regulatory Assets and Liabilities (Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012
Regulatory Assets And Liabilities [Line Items]
Regulatory assets represented past expenditures not earning return	$ 129
Period expenditures expected to be recovered (years)	2 years
DOE Claims	2,129	1,650
Virginia Electric and Power Company
Regulatory Assets And Liabilities [Line Items]
Regulatory assets represented past expenditures not earning return	63
DOE Claims	1,638	1,317
DOE Claims
Regulatory Assets And Liabilities [Line Items]
DOE Claims	$ 5