Employee Benefit Plans (Narrative) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended			12 Months Ended						3 Months Ended
	Dec. 31, 2013		Jun. 30, 2013	Dec. 31, 2014		Dec. 31, 2013		Dec. 31, 2012		Sep. 30, 2014
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Actual return on plan assets				$ 706		$ 959
Expected return on pension and other postretirement plan assets				610		554
Federal subsidy received				4		5
Decrease in other postretirement benefit obligations due to federal subsidy				20
Net actuarial loss				25
Reduction in net periodic benefit cost for next year	8		36
Reduction in accumulated postretirement benefit obligation	220					220
Period for reduction in net periodic benefit cost						5 years
Accumulated benefit obligation	5,100			6,000		5,100
Estimated reduction in net cumulative required contributions				200
Cumulative required contribution period (years)				10 years
Expected contribution to voluntary employees beneficiary association				12
Percentage coverage of US stock market				7.00%
Employer contributions				41		40		40
U.S. equity:
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Defined benefit plan, actual plan asset allocations				28.00%
Non-U.S. equity:
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Defined benefit plan, actual plan asset allocations				18.00%
Fixed Income
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Defined benefit plan, actual plan asset allocations				33.00%
Real estate:
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Defined benefit plan, actual plan asset allocations				3.00%
Other alternative investments
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Defined benefit plan, actual plan asset allocations				18.00%
Minimum
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Expected reduction in net periodic benefit cost						40
Investment grade bonds average weighted maturity period				4 years
Maximum
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Expected reduction in net periodic benefit cost						60
Investment grade bonds average weighted maturity period				12 years
Virginia Electric and Power Company
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Employer contributions				17		16		15
Virginia Electric and Power Company | Other operations and maintenance expense
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Net periodic benefit cost				75		96		72
Virginia Electric and Power Company | Dominion Retiree Health And Welfare Plan | Other operations and maintenance expense
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Net periodic benefit cost				(18)		5		13
Dominion Gas Holdings, LLC
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Actual return on plan assets				157		214
Expected return on pension and other postretirement plan assets				138		125
Federal subsidy received						1
Net actuarial loss				3
Reduction in net periodic benefit cost for next year			2
Accumulated benefit obligation	534			604		534
Employer contributions				7		7		6
Dominion Gas Holdings, LLC | Dominion Retiree Health And Welfare Plan | Multiemployer Plans, Postretirement Benefit
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Amount of contributions to VEBAs				1		2
Dominion Gas Holdings, LLC | Dominion Retiree Health And Welfare Plan | Multiemployer Plans, Postretirement Benefit | Other operations and maintenance expense
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Net periodic benefit cost				(5)		1		3
Pension Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Actual return on plan assets				601		781
Expected return on pension and other postretirement plan assets				499		462		430
Actuarial (gains) losses during the year				131
Net actuarial loss				160
Medicare Part D reimbursement			354
Discount rate			4.80%	5.30%
Reduction in accumulated postretirement benefit obligation	(22)	[1]		(1)	[1]	(22)	[1]	0	[1]
Discount rate								5.50%
Expected long-term rate of return on plan assets				8.75%		8.50%		8.50%
Net periodic benefit cost				20		106		89
Employer contributions				15		8
Pension Benefits | Minimum
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Discount rate	5.20%	[2]		4.40%	[2]	5.20%	[2]
Discount rate				5.20%		4.40%
Pension Benefits | Maximum
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Discount rate	5.30%	[2]				5.30%	[2]
Discount rate				5.30%		4.80%
Pension Benefits | Dominion Gas Holdings, LLC
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Actual return on plan assets				136		176
Expected return on pension and other postretirement plan assets				115		106		96
Actuarial (gains) losses during the year				10
Net actuarial loss				20
Medicare Part D reimbursement			28
Discount rate	5.20%			4.40%		5.20%
Discount rate				5.20%				5.50%
Expected long-term rate of return on plan assets				8.75%		8.50%		8.50%
Net periodic benefit cost				(55)		(39)		(30)
Employer contributions				0		0
Pension Benefits | Dominion Gas Holdings, LLC | Other operations and maintenance expense
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Net periodic benefit cost				(37)		(27)		(25)
Pension Benefits | Dominion Gas Holdings, LLC | Minimum
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Discount rate						4.40%
Pension Benefits | Dominion Gas Holdings, LLC | Maximum
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Discount rate						4.80%
Other Postretirement Benefits
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Actual return on plan assets				105		178
Expected return on pension and other postretirement plan assets				111		92		79
Actuarial (gains) losses during the year				32
Net actuarial loss				6
Medicare Part D reimbursement			78
Discount rate	4.80%		4.70%	5.10%		4.80%
Reduction in accumulated postretirement benefit obligation	(7)	[1]		0	[1]	(7)	[1]	(2)	[1]
Discount rate								5.50%
Expected long-term rate of return on plan assets				8.50%		7.75%		7.75%
Net periodic benefit cost				(38)		2		33
Employer contributions				12		12
Other Postretirement Benefits | Minimum
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Discount rate	5.00%	[2]		4.40%	[2]	5.00%	[2]
Discount rate				4.20%		4.40%
Expected long-term rate of return on plan assets				7.75%
Other Postretirement Benefits | Maximum
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Discount rate	5.10%	[2]				5.10%	[2]
Discount rate				5.10%		4.80%
Expected long-term rate of return on plan assets				8.50%
Other Postretirement Benefits | Dominion Gas Holdings, LLC
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Actual return on plan assets				21		38
Expected return on pension and other postretirement plan assets				23		19		16
Actuarial (gains) losses during the year				7
Net actuarial loss				2
Medicare Part D reimbursement			9
Discount rate	5.00%			4.40%		5.00%
Discount rate								5.50%
Expected long-term rate of return on plan assets				8.50%		7.75%		7.75%
Net periodic benefit cost				(5)		(1)		2
Employer contributions				10		10
Other Postretirement Benefits | Dominion Gas Holdings, LLC | Minimum
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Discount rate				4.20%		4.40%
Other Postretirement Benefits | Dominion Gas Holdings, LLC | Maximum
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Discount rate				5.00%		4.70%
Other Postretirement Benefits | East Ohio
Defined Benefit Plans and Other Postretirement Benefit Plans [Line Items]
Retirement age										65 years
Increase in accumulated postretirement benefit obligation due to amendment										22
Reduction in net periodic benefit credit due to amendment										$ 1
Discount rate										4.20%
Expected long-term rate of return on plan assets										8.50%

[1] 2013 amounts relate primarily to the decommissioning of Kewaunee.

[2] 2013 pension and other postretirement benefits discount rates: 5.20% and 5.00% for the gas union plans and 5.30% and 5.10% for the nonunion and other union plans, respectively.