Regulatory Matters (Narrative) (Details) (USD $)	9 Months Ended		1 Months Ended			9 Months Ended		1 Months Ended			6 Months Ended	12 Months Ended	3 Months Ended			1 Months Ended						12 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	May 31, 2012 Virginia Electric and Power Company	Mar. 31, 2010 Virginia Electric and Power Company	Apr. 30, 2008 Virginia Electric and Power Company	Sep. 30, 2014 Virginia Electric and Power Company	Sep. 30, 2013 Virginia Electric and Power Company	Sep. 30, 2014 Virginia Electric and Power Company Virginia Regulation	Aug. 31, 2013 Virginia Electric and Power Company Virginia Regulation motion	Apr. 30, 2014 Virginia Electric and Power Company Virginia Regulation North Anna	Jun. 30, 2014 Virginia Electric and Power Company Virginia Regulation North Anna	Dec. 31, 2013 Virginia Electric and Power Company Virginia Regulation North Anna	Sep. 30, 2014 Virginia Electric and Power Company Virginia Regulation North Anna Virginia legislation	Jun. 30, 2014 Virginia Electric and Power Company Virginia Regulation North Anna Virginia legislation	Dec. 31, 2014 Virginia Electric and Power Company Virginia Regulation Scenario, Forecast North Anna Virginia legislation	Nov. 30, 2014 Virginia Electric and Power Company Virginia Regulation Subsequent Event notice	Aug. 31, 2014 Virginia Electric and Power Company Virginia Regulation Riders C1A and C2A Program	Oct. 31, 2014 Virginia Electric and Power Company Virginia Regulation Rider BW Subsequent Event	Oct. 31, 2014 Virginia Electric and Power Company Virginia Regulation Rider U Subsequent Event	Aug. 31, 2014 Virginia Electric and Power Company North Carolina Regulation	Dec. 31, 2016 Virginia Electric and Power Company North Carolina Regulation Scenario, Forecast	Dec. 31, 2015 Virginia Electric and Power Company North Carolina Regulation Maximum Scenario, Forecast	Dec. 31, 2015 Virginia Electric and Power Company North Carolina Regulation Minimum Scenario, Forecast
Regulatory Matters [Line Items]
ROE					11.40%
Costs claimed to be unjust and excluded from transmission formula rate				$ 223,000,000
Potential settlement required annual payment for 10 Years						250,000
Settlement payment duration			10 years
Percentage deferred								50.00%													50.00%
Annual revenue increase								268,000,000									106,000,000					19,000,000	15,000,000
Approved increase amount								300,000,000
Proposed revenue requirement																	47,000,000		28,000,000
Number of new energy efficiency programs																	3
Requested cost cap period																	5 years
Approved revenue requirement																		111,000,000
Number motions for reconsideration filed									3
Number of appeal filed																3
Number of appeal withdrawn																2
Percentage of capitalized costs recovered										70.00%	70.00%
Deferred or capitalized costs	3,742,000,000	2,955,000,000				2,120,000,000	1,794,000,000					577,000,000
Charge associated with North Anna and offshore wind legislation	330,000,000	0				330,000,000	0						43,000,000	287,000,000	44,000,000
Charges associated with North Anna and offshore wind facilities, net of tax													28,000,000	191,000,000	29,000,000
Proposed fuel increase																				$ 25,000,000