Income Taxes (Tables)

12 Months Ended

Dec. 31, 2017

Income Taxes [Abstract]

Provision (Benefit) for Income Taxes

(in millions)		2017		2016		2015
Current:
Federal	$	(22)	$	(6)	$	1
State		–		(1)		(3)
		(22)		(7)		(2)
Deferred:
Federal		(71)		(22)		(1,697)
State		–		–		(304)
Foreign		–		–		(2)
		(71)		(22)		(2,003)
Benefit for income taxes	$	(93)	$	(29)	$	(2,005)

Reconciliation of Provision for Income Taxes

(in millions)	2017		2016		2015
Expected provision (benefit) at federal statutory rate	$	333	$	(935)	$	(2,296)
Increase (decrease) resulting from:
State income taxes, net of federal income tax effect		16		(79)		(194)
Nondeductible expenses		–		–		–
Rate impacts due to tax reform		370		–		–
Changes to valuation allowance due to tax reform		(370)		–		–
AMT tax reform impact – valuation allowance release		(68)		–		–
Change in uncertain tax positions		(5)		(19)		(7)
Change in valuation allowance		(364)		1,002		495
Other		(5)		2		(3)
Benefit for income taxes	$	(93)	$	(29)	$	(2,005)

Components of Deferred Tax Balances

(in millions)	2017		2016
Deferred tax liabilities:
Differences between book and tax basis of property	$	395	$	81
Derivative activity		19		–
Other		1		1
		415		82
Deferred tax assets:
Accrued compensation		29		38
Alternative minimum tax credit carryforward		–		100
Accrued pension costs		14		19
Asset retirement obligations		41		53
Net operating loss carryforward		1,043		1,177
Derivative activity		–		142
Other		20		29
		1,147		1,558
Valuation allowance		(732)		(1,476)
Net deferred tax liability	$	–	$	–

Reconciliation of Changes to the Valuation Allowance

		(in millions)
Valuation allowance as of December 31, 2016	$	1,476
Changes based on 2017 activity		(364)
Tax reform – rate change		(370)
Tax reform – AMT repeal		(68)
Release of prior uncertain tax position		(5)
Equity – windfall tax benefit release		59
Equity – pension benefits in OCI		4
Valuation allowance as of December 31, 2017	$	732

Reconciliation of Beginning and Ending Balances of Unrecognized Tax Benefits

(in millions)	2017		2016
Unrecognized tax benefits at beginning of period	$	17	$	37
Additions based on tax positions related to the current year		–		–
Additions to tax positions of prior years		–		–
Reductions to tax positions of prior years		(5)		(20)
Unrecognized tax benefits at end of period	$	12	$	17