Income Taxes (Tables)

12 Months Ended

Dec. 31, 2018

Schedule of components of the income tax provision (benefit)

The components of the income tax provision (benefit) for each of the periods presented below are as follows:



	Years Ended December 31,
	2018			2017			2016
	($ in millions)
Current
Federal	$	—		$	(14	)	$	(14	)
State	—			5			(5		)
Current Income Taxes	—			(9		)	(19		)
Deferred
Federal	3			13			(147		)
State	(13		)	(2		)	(24		)
Deferred Income Taxes	(10		)	11			(171		)
Total	$	(10	)	$	2		$	(190	)

Schedule of effective income tax expense (benefit)

The effective income tax expense (benefit) differed from the computed "expected" federal income tax expense on earnings before income taxes for the following reasons:



	Years Ended December 31,
	2018			2017			2016
	($ in millions)
Income tax expense (benefit) at the federal statutory rate (21%, 35%, 35%)	$	182		$	333		$	(1,606	)
State income taxes (net of federal income tax benefit)	23			66			(30		)
Remeasurement of deferred tax assets and liabilities	—			1,266			—
Change in valuation allowance	(230		)	(1,676		)	1,423
Other	15			13			23
Total	$	(10	)	$	2		$	(190	)

Schedule of deferred tax assets and liabilities

The tax-effected temporary differences, tax credits and net operating loss carryforwards that comprise our deferred taxes are as follows:



	Years Ended December 31,
	2018			2017
	($ in millions)
Deferred tax liabilities:
Property, plant and equipment	$	(544	)	$	—
Volumetric production payments	(117		)	(129		)
Carrying value of debt	(95		)	—
Derivative instruments	(56		)	—
Other	(7		)	(20		)
Deferred tax liabilities	(819		)	(149		)

Deferred tax assets:
Property, plant and equipment	—			1
Net operating loss carryforwards	2,737			2,248
Carrying value of debt	—			161
Disallowed business interest carryforward	194			—
Asset retirement obligations	40			42
Investments	132			161
Derivative instruments	—			17
Accrued liabilities	89			125
Other	60			71
Deferred tax assets	3,252			2,826
Valuation allowance	(2,433		)	(2,674		)
Net deferred tax assets	819			152
Net deferred tax assets	$	—		$	3

Reconciliation of unrecognized tax benefits

A reconciliation of the beginning and ending balances of unrecognized tax benefits is as follows:



	2018			2017			2016
	($ in millions)
Unrecognized tax benefits at beginning of period	$	106		$	202		$	280
Additions based on tax positions related to the current year	—			—			—
Additions to tax positions of prior years	—			4			33
Settlements	—			(100		)	(111		)
Expiration of the applicable statute of limitations	(23		)	—			—
Reductions to tax positions of prior years	(4		)	—			—
Unrecognized tax benefits at end of period	$	79		$	106		$	202