Income Taxes (Tables)

12 Months Ended

Dec. 31, 2016

Income Tax Disclosure [Abstract]

Income tax expense for continuing operations including noncontrolling interests

Details of income tax expense for continuing operations including noncontrolling interests were as follows:

	Dominion									Virginia Power									Dominion Gas
Year Ended December 31,	2016			2015			2014			2016			2015			2014			2016			2015		2014
(millions)
Current:
Federal	$	(155	)	$	(24	)	$	(11	)	$	168		$	316		$	85		$	(27	)	$	90	$	86
State	85			75			14			90			92			67			4			30		32
Total current expense (benefit)	(70		)	51			3			258			408			152			(23		)	120		118
Deferred:
Federal
Taxes before operating loss carryforwards and investment tax credits	1,050			384			956			435			154			381			239			156		192
Tax utilization (benefit) of operating loss carryforwards	(161		)	539			(352		)	(2		)	96			—			(2		)	6		—
Investment tax credits	(248		)	(134		)	(152		)	(25		)	(11		)	—			—			—		—
State	50			66			(2		)	27			13			16			1			1		24
Total deferred expense	691			855			450			435			252			397			238			163		216
Investment tax credit - gross deferral	35			—			—			35			—			—			—			—		—
Investment tax credit - amortization	(1		)	(1		)	(1		)	(1		)	(1		)	(1		)	—			—		—
Total income tax expense	$	655		$	905		$	452		$	727		$	659		$	548		$	215		$	283	$	334

Effective income tax

For continuing operations including noncontrolling interests, the statutory U.S. federal income tax rate reconciles to the Companies' effective income tax rate as follows:

	Dominion						Virginia Power						Dominion Gas
Year Ended December 31,	2016		2015		2014		2016		2015		2014		2016		2015		2014
U.S. statutory rate	35.0	%	35.0	%	35.0	%	35.0	%	35.0	%	35.0	%	35.0	%	35.0	%	35.0	%
Increases (reductions) resulting from:
State taxes, net of federal benefit	2.4		3.7		—		3.8		3.9		3.8		0.5		2.7		4.4
Investment tax credits	(11.7	)	(4.7	)	(8.6	)	—		(0.6	)	—		—		—		—
Production tax credits	(0.8	)	(0.8	)	(1.2	)	(0.6	)	(0.6	)	(0.6	)	—		—		—
Valuation allowances	1.2		(0.3	)	0.7		0.1		—		—		—		—		—
AFUDC - equity	(0.6	)	(0.3	)	—		(0.6	)	(0.6	)	—		(0.2	)	0.2		—
Legislative change	(0.6	)	(0.1	)	—		—		—		—		—
Employee stock ownership plan deduction	(0.6	)	(0.6	)	(0.9	)	—		—		—		—		—		—
Other, net	(1.4	)	0.1		0.4		(0.3	)	0.6		0.8		0.1		0.3		0.1
Effective tax rate	22.9	%	32.0	%	25.4	%	37.4	%	37.7	%	39.0	%	35.4	%	38.2	%	39.5	%

Deferred income taxes components

The Companies' deferred income taxes consist of the following:

	Dominion						Virginia Power						Dominion Gas
At December 31,	2016			2015			2016			2015			2016			2015
(millions)
Deferred income taxes:
Total deferred income tax assets	$	1,827		$	1,152		$	268		$	164		$	126		$	129
Total deferred income tax liabilities	10,381			8,552			5,323			4,805			2,564			2,343
Total net deferred income tax liabilities	$	8,554		$	7,400		$	5,055		$	4,641		$	2,438		$	2,214
Total deferred income taxes:
Plant and equipment, primarily depreciation method and basis differences	$	7,782		$	6,299		$	4,604		$	4,133		$	1,726		$	1,541
Nuclear decommissioning	1,240			1,158			406			378			—			—
Deferred state income taxes	747			646			321			302			204			205
Federal benefit of deferred state income taxes	(261		)	(226		)	(112		)	(106		)	(71		)	(72		)
Deferred fuel, purchased energy and gas costs	(25		)	(1		)	(29		)	(3		)	4			1
Pension benefits	155			291			(138		)	(99		)	646			613
Other postretirement benefits	(68		)	(15		)	49			30			(6		)	(7		)
Loss and credit carryforwards	(1,547		)	(1,004		)	(88		)	(53		)	(5		)	(4		)
Valuation allowances	135			73			3			—			—			—
Partnership basis differences	688			367			—			—			43			41
Other	(292		)	(188		)	39			59			(103		)	(104		)
Total net deferred income tax liabilities	$	8,554		$	7,400		$	5,055		$	4,641		$	2,438		$	2,214
Deferred investment tax credits - regulated operations	48			14			48			13			—			—
Total deferred taxes and deferred investment tax credits	$	8,602		$	7,414		$	5,103		$	4,654		$	2,438		$	2,214

Summary of deductible loss and credit carryforwards

At December 31, 2016, Dominion had the following deductible loss and credit carryforwards:

	Deductible amount		Deferred tax asset		Valuation allowance			Expiration period
(millions)
Federal losses	$	1,060	$	358	$	—		2031-2036
Federal investment credits	—		708		—			2033-2036
Federal production credits	—		102		—			2031-2036
Other federal credits	—		48		—			2031-2036
State losses	1,383		102		(59		)	2018-2034
State minimum tax credits	—		135		—			No expiration
State investment tax credits	—		94		(76		)	2017-2027
Total			$	1,547	$	(135	)

At December 31, 2016, Virginia Power had the following deductible loss and credit carryforwards:

	Deductible amount		Deferred tax asset		Valuation allowance			Expiration period
(millions)
Federal losses	$	12	$	3	$	—		2031-2034
Federal investment credits	—		40		—			2034-2036
Federal production and other credits	—		35		—			2031-2036
State investment credits	—		10		(3		)	2018-2024
Total			$	88	$	(3	)

At December 31, 2016, Dominion Gas had the following deductible loss and credit carryforwards:

	Deductible amount		Deferred tax asset		Valuation allowance		Expiration period
(millions)
Federal losses	$	14	$	4	$	—	2031-2036
Other federal credits	—		1		—		2032-2035
Total			$	5	$	—

Reconciliation of changes in unrecognized tax benefits

A reconciliation of changes in the Companies' unrecognized tax benefits follows:

	Dominion									Virginia Power									Dominion Gas
	2016			2015			2014			2016			2015			2014			2016			2015		2014
(millions)
Balance at January 1	$	103		$	145		$	222		$	12		$	36		$	39		$	29		$	29	$	29
Increases-prior period positions	9			2			24			4			—			2			1			—		—
Decreases-prior period positions	(44		)	(40		)	(26		)	(3		)	(25		)	(16		)	(19		)	—		—
Increases-current period positions	6			8			16			—			1			11			—			—		—
Settlements with tax authorities	(8		)	(5		)	—			—			—			—			(4		)	—		—
Expiration of statutes of limitations	(2		)	(7		)	(91		)	—			—			—			—			—		—
Balance at December 31	$	64		$	103		$	145		$	13		$	12		$	36		$	7		$	29	$	29

Earliest tax year remaining

For each of the major states in which Dominion operates, the earliest tax year remaining open for examination is as follows:

State	Earliest Open Tax Year
Pennsylvania(1)	2012
Connecticut	2013
Virginia(2)	2013
West Virginia(1)	2013
New York(1)	2007

(1) Considered a major state for Dominion Gas' operations.

(2) Considered a major state for Virginia Power's operations.