Employee Benefit Plans (Fair values of pension and post retirement plan assets by asset category) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014		Dec. 31, 2013
Pension Benefits
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	$ 6,469	[1]	$ 6,113	[1]
Pending sales of securities	31
Net accrued income	18
Pending purchases of securities	38
Pension Benefits | Cash equivalents and other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	38		179
Pension Benefits | U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	1,313		1,220
Pension Benefits | U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	530		514
Pension Benefits | Non-U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	234		308
Pension Benefits | Non-U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	403		391
Pension Benefits | Common/collective trust funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	1,595	[2]	1,387	[2]
Pension Benefits | Fixed Income: | Corporate debt instruments
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	711		494
Pension Benefits | Fixed Income: | U.S. Treasury securities and agency debentures
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	416		231
Pension Benefits | Fixed Income: | State and municipal
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	70		176
Pension Benefits | Fixed Income: | Other securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	86		57
Pension Benefits | Real estate: | REITs
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	40		32
Pension Benefits | Real estate: | Partnerships
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	209		227
Pension Benefits | Other alternative investments: | Private equity
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	518		530
Pension Benefits | Other alternative investments: | Debt
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	144		180
Pension Benefits | Other alternative investments: | Hedge funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	162		187
Pension Benefits | Level 1
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	2,668	[1]	2,639	[1]
Pension Benefits | Level 1 | Cash equivalents and other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	13		53
Pension Benefits | Level 1 | U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	1,313		1,220
Pension Benefits | Level 1 | U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	530		514
Pension Benefits | Level 1 | Non-U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	234		308
Pension Benefits | Level 1 | Non-U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	403		391
Pension Benefits | Level 1 | Common/collective trust funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0	[2]	0	[2]
John Hancock insurance contracts held	360		560
Pension Benefits | Level 1 | Fixed Income: | Corporate debt instruments
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	45		43
Pension Benefits | Level 1 | Fixed Income: | U.S. Treasury securities and agency debentures
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	74		2
Pension Benefits | Level 1 | Fixed Income: | State and municipal
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	10		69
Pension Benefits | Level 1 | Fixed Income: | Other securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	6		7
Pension Benefits | Level 1 | Real estate: | REITs
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	40		32
Pension Benefits | Level 1 | Real estate: | Partnerships
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 1 | Other alternative investments: | Private equity
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 1 | Other alternative investments: | Debt
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 1 | Other alternative investments: | Hedge funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 2
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	2,768	[1]	2,350	[1]
Pension Benefits | Level 2 | Cash equivalents and other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	25		126
Pension Benefits | Level 2 | U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 2 | U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 2 | Non-U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 2 | Non-U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 2 | Common/collective trust funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	1,595	[2]	1,387	[2]
Pension Benefits | Level 2 | Fixed Income: | Corporate debt instruments
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	666		451
Pension Benefits | Level 2 | Fixed Income: | U.S. Treasury securities and agency debentures
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	342		229
Pension Benefits | Level 2 | Fixed Income: | State and municipal
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	60		107
Pension Benefits | Level 2 | Fixed Income: | Other securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	80		50
Pension Benefits | Level 2 | Real estate: | REITs
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 2 | Real estate: | Partnerships
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 2 | Other alternative investments: | Private equity
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 2 | Other alternative investments: | Debt
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 2 | Other alternative investments: | Hedge funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 3
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	1,033	[1]	1,124	[1]
Pension Benefits | Level 3 | Cash equivalents and other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 3 | U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 3 | U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 3 | Non-U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 3 | Non-U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 3 | Common/collective trust funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0	[2]	0	[2]
Pension Benefits | Level 3 | Fixed Income: | Corporate debt instruments
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 3 | Fixed Income: | U.S. Treasury securities and agency debentures
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 3 | Fixed Income: | State and municipal
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 3 | Fixed Income: | Other securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 3 | Real estate: | REITs
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Level 3 | Real estate: | Partnerships
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	209		227
Pension Benefits | Level 3 | Other alternative investments: | Private equity
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	518		530
Pension Benefits | Level 3 | Other alternative investments: | Debt
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	144		180
Pension Benefits | Level 3 | Other alternative investments: | Hedge funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	162		187
Pension Benefits | Dominion Gas Holdings, LLC
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	1,508	[3]	1,403	[3]
Pending sales of securities	7
Net accrued income	4
Pending purchases of securities	9
Pension Benefits | Dominion Gas Holdings, LLC | Cash equivalents and other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	9		41
Pension Benefits | Dominion Gas Holdings, LLC | U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	306		280
Pension Benefits | Dominion Gas Holdings, LLC | U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	124		118
Pension Benefits | Dominion Gas Holdings, LLC | Non-U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	54		72
Pension Benefits | Dominion Gas Holdings, LLC | Non-U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	94		90
Pension Benefits | Dominion Gas Holdings, LLC | Common/collective trust funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	372	[4]	318	[4]
Pension Benefits | Dominion Gas Holdings, LLC | Fixed Income: | Corporate debt instruments
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	166		113
Pension Benefits | Dominion Gas Holdings, LLC | Fixed Income: | U.S. Treasury securities and agency debentures
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	97		53
Pension Benefits | Dominion Gas Holdings, LLC | Fixed Income: | State and municipal
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	16		40
Pension Benefits | Dominion Gas Holdings, LLC | Fixed Income: | Other securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	20		13
Pension Benefits | Dominion Gas Holdings, LLC | Real estate: | REITs
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	9		7
Pension Benefits | Dominion Gas Holdings, LLC | Real estate: | Partnerships
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	48		52
Pension Benefits | Dominion Gas Holdings, LLC | Other alternative investments: | Private equity
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	121		122
Pension Benefits | Dominion Gas Holdings, LLC | Other alternative investments: | Debt
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	34		41
Pension Benefits | Dominion Gas Holdings, LLC | Other alternative investments: | Hedge funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	38		43
Pension Benefits | Dominion Gas Holdings, LLC | Level 1
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	621	[3]	608	[3]
Pension Benefits | Dominion Gas Holdings, LLC | Level 1 | Cash equivalents and other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	3		12
Pension Benefits | Dominion Gas Holdings, LLC | Level 1 | U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	306		280
Pension Benefits | Dominion Gas Holdings, LLC | Level 1 | U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	124		118
Pension Benefits | Dominion Gas Holdings, LLC | Level 1 | Non-U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	54		72
Pension Benefits | Dominion Gas Holdings, LLC | Level 1 | Non-U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	94		90
Pension Benefits | Dominion Gas Holdings, LLC | Level 1 | Common/collective trust funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0	[4]	0	[4]
Pension Benefits | Dominion Gas Holdings, LLC | Level 1 | Fixed Income: | Corporate debt instruments
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	11		10
Pension Benefits | Dominion Gas Holdings, LLC | Level 1 | Fixed Income: | U.S. Treasury securities and agency debentures
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	17		1
Pension Benefits | Dominion Gas Holdings, LLC | Level 1 | Fixed Income: | State and municipal
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	2		16
Pension Benefits | Dominion Gas Holdings, LLC | Level 1 | Fixed Income: | Other securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	1		2
Pension Benefits | Dominion Gas Holdings, LLC | Level 1 | Real estate: | REITs
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	9		7
Pension Benefits | Dominion Gas Holdings, LLC | Level 1 | Real estate: | Partnerships
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 1 | Other alternative investments: | Private equity
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 1 | Other alternative investments: | Debt
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 1 | Other alternative investments: | Hedge funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 2
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	646	[3]	537	[3]
Pension Benefits | Dominion Gas Holdings, LLC | Level 2 | Cash equivalents and other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	6		29
Pension Benefits | Dominion Gas Holdings, LLC | Level 2 | U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 2 | U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 2 | Non-U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 2 | Non-U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 2 | Common/collective trust funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	372	[4]	318	[4]
Pension Benefits | Dominion Gas Holdings, LLC | Level 2 | Fixed Income: | Corporate debt instruments
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	155		103
Pension Benefits | Dominion Gas Holdings, LLC | Level 2 | Fixed Income: | U.S. Treasury securities and agency debentures
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	80		52
Pension Benefits | Dominion Gas Holdings, LLC | Level 2 | Fixed Income: | State and municipal
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	14		24
Pension Benefits | Dominion Gas Holdings, LLC | Level 2 | Fixed Income: | Other securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	19		11
Pension Benefits | Dominion Gas Holdings, LLC | Level 2 | Real estate: | REITs
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 2 | Real estate: | Partnerships
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 2 | Other alternative investments: | Private equity
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 2 | Other alternative investments: | Debt
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 2 | Other alternative investments: | Hedge funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 3
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	241	[3]	258	[3]
Pension Benefits | Dominion Gas Holdings, LLC | Level 3 | Cash equivalents and other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 3 | U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 3 | U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 3 | Non-U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 3 | Non-U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 3 | Common/collective trust funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0	[4]	0	[4]
Pension Benefits | Dominion Gas Holdings, LLC | Level 3 | Fixed Income: | Corporate debt instruments
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 3 | Fixed Income: | U.S. Treasury securities and agency debentures
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 3 | Fixed Income: | State and municipal
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 3 | Fixed Income: | Other securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 3 | Real estate: | REITs
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Pension Benefits | Dominion Gas Holdings, LLC | Level 3 | Real estate: | Partnerships
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	48		52
Pension Benefits | Dominion Gas Holdings, LLC | Level 3 | Other alternative investments: | Private equity
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	121		122
Pension Benefits | Dominion Gas Holdings, LLC | Level 3 | Other alternative investments: | Debt
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	34		41
Pension Benefits | Dominion Gas Holdings, LLC | Level 3 | Other alternative investments: | Hedge funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	38		43
Other Postretirement Plans
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	1,402		1,315
Other Postretirement Plans | Cash equivalents and other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	8		17
Other Postretirement Plans | U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	514		472
Other Postretirement Plans | U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	28		26
Other Postretirement Plans | Non-U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	102		111
Other Postretirement Plans | Non-U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	21		20
Other Postretirement Plans | Common/collective trust funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	555	[5]	502	[5]
Other Postretirement Plans | Fixed Income: | Corporate debt instruments
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	38		25
Other Postretirement Plans | Fixed Income: | U.S. Treasury securities and agency debentures
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	22		12
Other Postretirement Plans | Fixed Income: | State and municipal
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	4		9
Other Postretirement Plans | Fixed Income: | Other securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	4		3
Other Postretirement Plans | Real estate: | REITs
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	2		2
Other Postretirement Plans | Real estate: | Partnerships
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	19		19
Other Postretirement Plans | Other alternative investments: | Private equity
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	58		60
Other Postretirement Plans | Other alternative investments: | Debt
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	18		27
Other Postretirement Plans | Other alternative investments: | Hedge funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	9		10
Other Postretirement Plans | Level 1
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	676		640
Other Postretirement Plans | Level 1 | Cash equivalents and other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	1		3
Other Postretirement Plans | Level 1 | U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	514		472
Other Postretirement Plans | Level 1 | U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	28		26
Other Postretirement Plans | Level 1 | Non-U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	102		111
Other Postretirement Plans | Level 1 | Non-U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	21		20
Other Postretirement Plans | Level 1 | Common/collective trust funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0	[5]	0	[5]
John Hancock insurance contracts held	19		29
Other Postretirement Plans | Level 1 | Fixed Income: | Corporate debt instruments
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	3		2
Other Postretirement Plans | Level 1 | Fixed Income: | U.S. Treasury securities and agency debentures
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	4		0
Other Postretirement Plans | Level 1 | Fixed Income: | State and municipal
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	1		4
Other Postretirement Plans | Level 1 | Fixed Income: | Other securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 1 | Real estate: | REITs
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	2		2
Other Postretirement Plans | Level 1 | Real estate: | Partnerships
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 1 | Other alternative investments: | Private equity
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 1 | Other alternative investments: | Debt
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 1 | Other alternative investments: | Hedge funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 2
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	622		559
Other Postretirement Plans | Level 2 | Cash equivalents and other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	7		14
Other Postretirement Plans | Level 2 | U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 2 | U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 2 | Non-U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 2 | Non-U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 2 | Common/collective trust funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	555	[5]	502	[5]
Other Postretirement Plans | Level 2 | Fixed Income: | Corporate debt instruments
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	35		23
Other Postretirement Plans | Level 2 | Fixed Income: | U.S. Treasury securities and agency debentures
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	18		12
Other Postretirement Plans | Level 2 | Fixed Income: | State and municipal
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	3		5
Other Postretirement Plans | Level 2 | Fixed Income: | Other securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	4		3
Other Postretirement Plans | Level 2 | Real estate: | REITs
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 2 | Real estate: | Partnerships
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 2 | Other alternative investments: | Private equity
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 2 | Other alternative investments: | Debt
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 2 | Other alternative investments: | Hedge funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 3
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	104		116
Other Postretirement Plans | Level 3 | Cash equivalents and other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 3 | U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 3 | U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 3 | Non-U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 3 | Non-U.S. equity: | Other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 3 | Common/collective trust funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0	[5]	0	[5]
Other Postretirement Plans | Level 3 | Fixed Income: | Corporate debt instruments
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 3 | Fixed Income: | U.S. Treasury securities and agency debentures
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 3 | Fixed Income: | State and municipal
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 3 | Fixed Income: | Other securities
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 3 | Real estate: | REITs
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Level 3 | Real estate: | Partnerships
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	19		19
Other Postretirement Plans | Level 3 | Other alternative investments: | Private equity
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	58		60
Other Postretirement Plans | Level 3 | Other alternative investments: | Debt
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	18		27
Other Postretirement Plans | Level 3 | Other alternative investments: | Hedge funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	9		10
Other Postretirement Plans | Dominion Gas Holdings, LLC
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	288		273
Other Postretirement Plans | Dominion Gas Holdings, LLC | Cash equivalents and other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	2		3
Other Postretirement Plans | Dominion Gas Holdings, LLC | U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	113		104
Other Postretirement Plans | Dominion Gas Holdings, LLC | Non-U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	26		26
Other Postretirement Plans | Dominion Gas Holdings, LLC | Common/collective trust funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	129	[4]	119	[4]
Other Postretirement Plans | Dominion Gas Holdings, LLC | Real estate: | Partnerships
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	2		2
Other Postretirement Plans | Dominion Gas Holdings, LLC | Other alternative investments: | Private equity
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	12		12
Other Postretirement Plans | Dominion Gas Holdings, LLC | Other alternative investments: | Debt
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	4		7
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 1
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	139		130
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 1 | Cash equivalents and other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 1 | U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	113		104
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 1 | Non-U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	26		26
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 1 | Common/collective trust funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0	[4]	0	[4]
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 1 | Real estate: | Partnerships
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 1 | Other alternative investments: | Private equity
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 1 | Other alternative investments: | Debt
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 2
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	131		122
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 2 | Cash equivalents and other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	2		3
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 2 | U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 2 | Non-U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 2 | Common/collective trust funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	129	[4]	119	[4]
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 2 | Real estate: | Partnerships
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 2 | Other alternative investments: | Private equity
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 2 | Other alternative investments: | Debt
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 3
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	18		21
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 3 | Cash equivalents and other
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 3 | U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 3 | Non-U.S. equity: | Large Cap
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0		0
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 3 | Common/collective trust funds
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	0	[4]	0	[4]
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 3 | Real estate: | Partnerships
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	2		2
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 3 | Other alternative investments: | Private equity
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	12		12
Other Postretirement Plans | Dominion Gas Holdings, LLC | Level 3 | Other alternative investments: | Debt
Defined Benefit Plan Disclosure [Line Items]
Pension plan assets by asset category	$ 4		$ 7

[1] Includes net assets related to pending sales of securities of $31 million, net accrued income of $18 million, and excludes net assets related to pending purchases of securities of $38 million at December 31, 2014.

[2] Common/Collective Trust Funds include $360 million and $560 million of John Hancock insurance contracts held at December 31, 2014 and 2013, respectively. See below for a description of the individual investments included within this line item, and the nature and risk of each respective fund.

[3] Includes net assets related to pending sales of securities of $7 million, net accrued income of $4 million, and excludes net assets related to pending purchases of securities of $9 million at December 31, 2014.

[4] See below for a description of the individual investments included within this line item, and the nature and risk of each respective fund.

[5] Common/Collective Trust Funds include $19 million and $29 million of John Hancock insurance contracts held at December 31, 2014 and 2013, respectively. See below for a description of the individual investments included within this line item, and the nature and risk of each respective fund.