Shareholders' Equity (Schedule of Components of Accumulated Other Comprehensive Income) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012	Dec. 31, 2011
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	$ (877)
Other comprehensive income before reclassifications: gains (losses)	476
Amounts reclassified from accumulated other comprehensive income: (gains) losses	77	[1]
Total other comprehensive income income (loss)	553		(267)	(280)
Ending balance	(324)		(877)
Deferred gains and losses on derivatives-hedging activities
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(122)
Other comprehensive income before reclassifications: gains (losses)	(243)
Amounts reclassified from accumulated other comprehensive income: (gains) losses	77	[1]
Total other comprehensive income income (loss)	(166)
Ending balance	(288)
Unrealized gains and losses on investment securities
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	326
Other comprehensive income before reclassifications: gains (losses)	203
Amounts reclassified from accumulated other comprehensive income: (gains) losses	(55)	[1]
Total other comprehensive income income (loss)	148
Ending balance	474
Unrecognized pension and other postretirement benefit costs
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(1,081)
Other comprehensive income before reclassifications: gains (losses)	516
Amounts reclassified from accumulated other comprehensive income: (gains) losses	55	[1]
Total other comprehensive income income (loss)	571
Ending balance	(510)
Virginia Electric and Power Company
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	25
Other comprehensive income before reclassifications: gains (losses)	26
Amounts reclassified from accumulated other comprehensive income: (gains) losses	(3)	[1]
Total other comprehensive income income (loss)	23		6	(5)
Ending balance	48		25
Virginia Electric and Power Company | Deferred gains and losses on derivatives-hedging activities
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	(6)
Other comprehensive income before reclassifications: gains (losses)	6
Amounts reclassified from accumulated other comprehensive income: (gains) losses	0	[1]
Total other comprehensive income income (loss)	6
Ending balance	0
Virginia Electric and Power Company | Unrealized gains and losses on investment securities
Accumulated Other Comprehensive Income (Loss) [Roll Forward]
Beginning balance	31
Other comprehensive income before reclassifications: gains (losses)	20
Amounts reclassified from accumulated other comprehensive income: (gains) losses	(3)	[1]
Total other comprehensive income income (loss)	17
Ending balance	$ 48

[1] See table below for details about these reclassifications.