Fair Value Measurements (Assets and Liabilities that are Measured at Fair Value on a Recurring Basis) (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015		Dec. 31, 2014
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	$ 679		$ 719
Derivative Liabilities	765		794
Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	94
Derivative Liabilities	18
Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	4,959	[1]	4,938	[1]
Total liabilities	765		794
Fair Value, Measurements, Recurring | Commodity
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	661		695
Derivative Liabilities	458		592
Fair Value, Measurements, Recurring | Interest rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	18		24
Derivative Liabilities	307		202
Fair Value, Measurements, Recurring | Equity securities: | Large cap | U.S.:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	2,647	[1]	2,669	[1]
Fair Value, Measurements, Recurring | Equity securities: | Large cap | Non-U.S.:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	12	[1]	12	[1]
Fair Value, Measurements, Recurring | Equity securities: | Other | U.S.:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	7	[1]	6	[1]
Fair Value, Measurements, Recurring | Fixed income: | Corporate debt instruments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	462	[1]	441	[1]
Fair Value, Measurements, Recurring | Fixed income: | U.S. Treasury securities and agency debentures
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	594	[1]	609	[1]
Fair Value, Measurements, Recurring | Fixed income: | State and municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	423	[1]	395	[1]
Fair Value, Measurements, Recurring | Fixed income: | Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	130	[1]	74	[1]
Fair Value, Measurements, Recurring | Cash equivalents and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	5	[1]	13	[1]
Fair Value, Measurements, Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	3,077	[1]	3,112	[1]
Total liabilities	3		3
Fair Value, Measurements, Recurring | Level 1 | Commodity
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	3		3
Derivative Liabilities	3		3
Fair Value, Measurements, Recurring | Level 1 | Interest rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	0		0
Derivative Liabilities	0		0
Fair Value, Measurements, Recurring | Level 1 | Equity securities: | Large cap | U.S.:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	2,647	[1]	2,669	[1]
Fair Value, Measurements, Recurring | Level 1 | Equity securities: | Large cap | Non-U.S.:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	12	[1]	12	[1]
Fair Value, Measurements, Recurring | Level 1 | Equity securities: | Other | U.S.:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	7	[1]	6	[1]
Fair Value, Measurements, Recurring | Level 1 | Fixed income: | Corporate debt instruments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Fair Value, Measurements, Recurring | Level 1 | Fixed income: | U.S. Treasury securities and agency debentures
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	407	[1]	419	[1]
Fair Value, Measurements, Recurring | Level 1 | Fixed income: | State and municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Fair Value, Measurements, Recurring | Level 1 | Fixed income: | Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Fair Value, Measurements, Recurring | Level 1 | Cash equivalents and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	1	[1]	3	[1]
Fair Value, Measurements, Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	1,788	[1]	1,701	[1]
Total liabilities	744		773
Fair Value, Measurements, Recurring | Level 2 | Commodity
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	564		567
Derivative Liabilities	437		571
Fair Value, Measurements, Recurring | Level 2 | Interest rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	18		24
Derivative Liabilities	307		202
Fair Value, Measurements, Recurring | Level 2 | Equity securities: | Large cap | U.S.:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Fair Value, Measurements, Recurring | Level 2 | Equity securities: | Large cap | Non-U.S.:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Fair Value, Measurements, Recurring | Level 2 | Equity securities: | Other | U.S.:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Fair Value, Measurements, Recurring | Level 2 | Fixed income: | Corporate debt instruments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	462	[1]	441	[1]
Fair Value, Measurements, Recurring | Level 2 | Fixed income: | U.S. Treasury securities and agency debentures
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	187	[1]	190	[1]
Fair Value, Measurements, Recurring | Level 2 | Fixed income: | State and municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	423	[1]	395	[1]
Fair Value, Measurements, Recurring | Level 2 | Fixed income: | Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	130	[1]	74	[1]
Fair Value, Measurements, Recurring | Level 2 | Cash equivalents and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	4	[1]	10	[1]
Fair Value, Measurements, Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	94	[1]	125	[1]
Total liabilities	18		18
Fair Value, Measurements, Recurring | Level 3 | Commodity
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	94		125
Derivative Liabilities	18		18
Fair Value, Measurements, Recurring | Level 3 | Interest rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	0		0
Derivative Liabilities	0		0
Fair Value, Measurements, Recurring | Level 3 | Equity securities: | Large cap | U.S.:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Fair Value, Measurements, Recurring | Level 3 | Equity securities: | Large cap | Non-U.S.:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Fair Value, Measurements, Recurring | Level 3 | Equity securities: | Other | U.S.:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Fair Value, Measurements, Recurring | Level 3 | Fixed income: | Corporate debt instruments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Fair Value, Measurements, Recurring | Level 3 | Fixed income: | U.S. Treasury securities and agency debentures
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Fair Value, Measurements, Recurring | Level 3 | Fixed income: | State and municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Fair Value, Measurements, Recurring | Level 3 | Fixed income: | Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Fair Value, Measurements, Recurring | Level 3 | Cash equivalents and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Virginia Electric and Power Company
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	106		113
Derivative Liabilities	139		87
Virginia Electric and Power Company | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	82
Derivative Liabilities	4
Virginia Electric and Power Company | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	1,977	[1]	1,952	[1]
Total liabilities	139		87
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Commodity
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	106		113
Derivative Liabilities	11		15
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Interest rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liabilities	128		72
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Equity securities: | Large cap | U.S.:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	1,166	[1]	1,157	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Fixed income: | Corporate debt instruments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	258	[1]	250	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Fixed income: | U.S. Treasury securities and agency debentures
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	192	[1]	198	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Fixed income: | State and municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	224	[1]	211	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Fixed income: | Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	31	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Cash equivalents and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments			23	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	1,295	[1]	1,294	[1]
Total liabilities	0		0
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 1 | Commodity
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	0		0
Derivative Liabilities	0		0
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 1 | Interest rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liabilities	0		0
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 1 | Equity securities: | Large cap | U.S.:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	1,166	[1]	1,157	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 1 | Fixed income: | Corporate debt instruments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 1 | Fixed income: | U.S. Treasury securities and agency debentures
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	129	[1]	137	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 1 | Fixed income: | State and municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 1 | Fixed income: | Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 1 | Cash equivalents and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments			0	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	600	[1]	552	[1]
Total liabilities	135		83
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 2 | Commodity
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	24		7
Derivative Liabilities	7		11
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 2 | Interest rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liabilities	128		72
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 2 | Equity securities: | Large cap | U.S.:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 2 | Fixed income: | Corporate debt instruments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	258	[1]	250	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 2 | Fixed income: | U.S. Treasury securities and agency debentures
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	63	[1]	61	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 2 | Fixed income: | State and municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	224	[1]	211	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 2 | Fixed income: | Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	31	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 2 | Cash equivalents and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments			23	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	82	[1]	106	[1]
Total liabilities	4		4
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 3 | Commodity
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	82		106
Derivative Liabilities	4		4
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 3 | Interest rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liabilities	0		0
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 3 | Equity securities: | Large cap | U.S.:
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 3 | Fixed income: | Corporate debt instruments
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 3 | Fixed income: | U.S. Treasury securities and agency debentures
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 3 | Fixed income: | State and municipal
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]	0	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 3 | Fixed income: | Other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments	0	[1]
Virginia Electric and Power Company | Fair Value, Measurements, Recurring | Level 3 | Cash equivalents and other
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Investments			0	[1]
Dominion Gas Holdings, LLC | Fair Value, Measurements, Recurring
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	3		2
Total liabilities	16
Dominion Gas Holdings, LLC | Fair Value, Measurements, Recurring | Commodity
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	3		2
Derivative Liabilities	3		9
Dominion Gas Holdings, LLC | Fair Value, Measurements, Recurring | Interest rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liabilities	13		9
Dominion Gas Holdings, LLC | Fair Value, Measurements, Recurring | Level 1
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0		0
Total liabilities	0
Dominion Gas Holdings, LLC | Fair Value, Measurements, Recurring | Level 1 | Commodity
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	0		0
Derivative Liabilities	0		0
Dominion Gas Holdings, LLC | Fair Value, Measurements, Recurring | Level 1 | Interest rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liabilities	0		0
Dominion Gas Holdings, LLC | Fair Value, Measurements, Recurring | Level 2
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	3		0
Total liabilities	16
Dominion Gas Holdings, LLC | Fair Value, Measurements, Recurring | Level 2 | Commodity
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	3		0
Derivative Liabilities	3		9
Dominion Gas Holdings, LLC | Fair Value, Measurements, Recurring | Level 2 | Interest rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liabilities	13		9
Dominion Gas Holdings, LLC | Fair Value, Measurements, Recurring | Level 3
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Total assets	0		2
Total liabilities	0
Dominion Gas Holdings, LLC | Fair Value, Measurements, Recurring | Level 3 | Commodity
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Asset	0		2
Derivative Liabilities	0		0
Dominion Gas Holdings, LLC | Fair Value, Measurements, Recurring | Level 3 | Interest rate
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Derivative Liabilities	$ 0		$ 0

[1] Includes investments held in the nuclear decommissioning and rabbi trusts.