Fair Value Measurements (Financial Instruments' Carrying Amounts and Fair Values) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2013		Dec. 31, 2012
Junior subordinated notes	$ 1,373		$ 1,373	[1]
Subsidiary preferred stock	257		257	[1]
Valuation of certain fair value hedges	72		93
Issuance expenses of subsidiary preferred stock	2		2
Carrying Amount
Long-term debt, including securities due within one year	17,097	[2]	16,841	[2]
Securities due within one year, VIE	852	[3]	860	[3]
Junior subordinated notes	1,373		1,373
Subsidiary preferred stock	257	[4]	257	[4]
Estimate of Fair Value
Long-term debt, including securities due within one year	19,874	[2]	19,898	[2],[5]
Securities due within one year, VIE	855	[3]	864	[3],[5]
Junior subordinated notes	1,435		1,430	[5]
Subsidiary preferred stock	260	[4]	255	[4],[5]
Virginia Electric and Power Company
Subsidiary preferred stock	257		257	[6]
Virginia Electric and Power Company | Carrying Amount
Long-term debt, including securities due within one year	7,463	[2]	6,669	[2]
Subsidiary preferred stock	257	[4]	257	[4]
Virginia Electric and Power Company | Estimate of Fair Value
Long-term debt, including securities due within one year	8,929	[2]	8,270	[2],[5]
Subsidiary preferred stock	$ 260	[4]	$ 255	[4],[5]

[1] Dominion’s Consolidated Balance Sheet at December 31, 2012 has been derived from the audited Consolidated Financial Statements at that date.

[2] Includes amounts which represent the unamortized discount and premium. At March 31, 2013 and December 31, 2012, includes the valuation of certain fair value hedges associated with Dominion’s fixed rate debt of approximately $72 million and $93 million, respectively.

[3] Includes amounts which represent the unamortized premium.

[4] Includes deferred issuance expenses of $2 million at March 31, 2013 and December 31, 2012.

[5] Fair value is estimated using market prices, where available, and interest rates currently available for issuance of debt with similar terms and remaining maturities. All fair value measurements are classified as Level 2. The carrying amount of debt issues with short-term maturities and variable rates refinanced at current market rates is a reasonable estimate of their fair value.

[6] Virginia Power’s Consolidated Balance Sheet at December 31, 2012 has been derived from the audited Consolidated Financial Statements at that date.