Accumulated Other Comprehensive Income (Schedule of Reclassifications out of AOCI by Component Net of Tax) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2014		Sep. 30, 2013		Sep. 30, 2014		Sep. 30, 2013
Accumulated Other Comprehensive Income (Loss) [Line Items]
Operating Revenue	$ 3,050		$ 3,432		$ 9,493		$ 9,935
Purchased gas	209		232		1,073		996
Electric fuel and other energy-related purchases	743		1,107		2,710		2,933
Interest and related charges	231		217		695		648
Other income	69		86		166		222
Income from continuing operations including noncontrolling interests before income tax expense	759		903		1,554		2,086
Income tax expense	(228)		(305)		(477)		(709)
Income from continuing operations including noncontrolling interests	531		598		1,077		1,377
Dominion Gas Holdings, LLC
Accumulated Other Comprehensive Income (Loss) [Line Items]
Operating Revenue	391	[1]	388	[1]	1,388	[1]	1,404	[1]
Purchased gas	34	[1]	46	[1]	247	[1]	223	[1]
Interest and related charges	7	[1]	7	[1]	19	[1]	20	[1]
Other income	5		5		18		19
Income from continuing operations including noncontrolling interests before income tax expense	175		215		595		528
Income tax expense	(68)		(85)		(231)		(207)
Deferred gains and losses on derivatives-hedging activities | Amounts reclassified from AOCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income from continuing operations including noncontrolling interests before income tax expense	(53)		(10)		185		88
Income tax expense	22		4		(72)		(35)
Income from continuing operations including noncontrolling interests	(31)		(6)		113		53
Deferred gains and losses on derivatives-hedging activities | Amounts reclassified from AOCI | Dominion Gas Holdings, LLC
Accumulated Other Comprehensive Income (Loss) [Line Items]
Income from continuing operations including noncontrolling interests before income tax expense	6		5		18		9
Income tax expense	(2)		(2)		(7)		(3)
Income from continuing operations including noncontrolling interests	4		3		11		6
Unrealized gains and losses on investment securities | Amounts reclassified from AOCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Other income	(38)		(16)		(71)		(80)
Impairment	4		1		8		6
Income from continuing operations including noncontrolling interests before income tax expense	(34)		(15)		(63)		(74)
Income tax expense	13		5		24		28
Income from continuing operations including noncontrolling interests	(21)		(10)		(39)		(46)
Unrecognized pension and other postretirement benefit costs | Amounts reclassified from AOCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Prior service (credit) costs	(4)				(9)		(6)
Actuarial (gains) losses	18		23		52		79
Income from continuing operations including noncontrolling interests before income tax expense	14		23		43		73
Income tax expense	(6)		(9)		(18)		(29)
Income from continuing operations including noncontrolling interests	8		14		25		44
Unrecognized pension and other postretirement benefit costs | Amounts reclassified from AOCI | Dominion Gas Holdings, LLC
Accumulated Other Comprehensive Income (Loss) [Line Items]
Actuarial (gains) losses	2		2		5		7
Income from continuing operations including noncontrolling interests before income tax expense	2		2		5		7
Income tax expense	(1)		(1)		(2)		(3)
Income from continuing operations including noncontrolling interests	1		1		3		4
Commodity contracts | Deferred gains and losses on derivatives-hedging activities | Amounts reclassified from AOCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Operating Revenue	(66)		(24)		175		31
Purchased gas	3		5		7		39
Electric fuel and other energy-related purchases	5		3		(8)		6
Commodity contracts | Deferred gains and losses on derivatives-hedging activities | Amounts reclassified from AOCI | Dominion Gas Holdings, LLC
Accumulated Other Comprehensive Income (Loss) [Line Items]
Operating Revenue	1		1		8		(1)
Purchased gas	5		4		10		10
Interest rate contracts | Deferred gains and losses on derivatives-hedging activities | Amounts reclassified from AOCI
Accumulated Other Comprehensive Income (Loss) [Line Items]
Interest and related charges	$ 5		$ 6		$ 11		$ 12

[1] See Note 17 for amounts attributable to related parties.