Income Taxes (Income Tax Expense for Continuing Operations Including Noncontrolling Interests) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Current:
Federal	$ (24)	$ (11)	$ 317
State	75	14	110
Total current expense	51	3	427
Federal
Taxes before operating loss carryforwards and investment tax credits	384	956	563
Tax utilization (benefit) of operating loss carryforwards	539	(352)	(18)
Investment tax credits	(134)	(152)	(48)
State	66	(2)	(31)
Total deferred expense	855	450	466
Amortization of deferred investment tax credits	(1)	(1)	(1)
Total income tax expense	905	452	892
Virginia Electric and Power Company
Current:
Federal	316	85	357
State	92	67	62
Total current expense	408	152	419
Federal
Taxes before operating loss carryforwards and investment tax credits	154	381	224
Tax utilization (benefit) of operating loss carryforwards	96	0	0
Investment tax credits	(11)	0	0
State	13	16	17
Total deferred expense	252	397	241
Amortization of deferred investment tax credits	(1)	(1)	(1)
Total income tax expense	659	548	659
Dominion Gas Holdings, LLC
Current:
Federal	90	86	158
State	30	32	41
Total current expense	120	118	199
Federal
Taxes before operating loss carryforwards and investment tax credits	156	192	92
Tax utilization (benefit) of operating loss carryforwards	6	0	0
Investment tax credits	0	0	0
State	1	24	10
Total deferred expense	163	216	102
Amortization of deferred investment tax credits	0	0	0
Total income tax expense	$ 283	$ 334	$ 301