Income Taxes (Tables)

12 Months Ended

Dec. 31, 2020

Unrecognized tax benefit activity is as follows:


	Year Ended December 31,
	2020		2019		2018
	(in millions)
Beginning unrecognized tax benefits	$	39	$	141	$	124
Current year additions	—		—		17
Effectively settled tax positions	(39)		(102)		—
Ending unrecognized tax benefits	$	—	$	39	$	141

Summary of open tax years

The earliest open years in the Company's key jurisdictions are as follows:


U.S. federal			2016
Various U.S. states			2013

Income tax (provision) benefit attributable to continuing operations

is as follows:


	Year Ended December 31,
	2020		2019		2018
	(in millions)
Current:
U.S. federal	$	12	$	8	$	—
U.S. state	(3)		(3)		(2)
Current income tax benefit (provision)	9		5		(2)
Deferred:
U.S. federal	55		(228)		(258)
U.S. state	(3)		(12)		(16)
Deferred income tax benefit (provision)	52		(240)		(274)
Income tax benefit (provision)	$	61	$	(235)	$	(276)

Reconciliation of federal statutory tax rate

The effective tax rate for income (loss) is reconciled to the United States federal statutory rate as follows:


	Year Ended December 31,
	2020			2019			2018
	(in millions, except percentages)
Income (loss) before income taxes	$	(261)		$	1,008		$	1,251
Net loss attributable to noncontrolling interests	—			—			3
Income (loss) attributable to common stockholders before income taxes	$	(261)		$	1,008		$	1,254
Federal statutory income tax rate	21		%	21		%	21		%
Benefit (provision) for federal income taxes at the statutory rate	55			(212)			(263)
State income tax provision (net of federal tax)	(5)			(12)			(12)



Other	11			(11)			(1)
Income tax benefit (provision)	$	61		$	(235)		$	(276)
Effective income tax rate, excluding net loss attributable to noncontrolling interests	23		%	23		%	22		%

Schedule of deferred tax assets and liabilities

Significant components of deferred tax assets and deferred tax liabilities are as follows:


	As of December 31,
	2020		2019
	(in millions)
Deferred tax assets:
Net operating loss carryforward (a)	$	1,111	$	1,039
Credit carryforwards (b)	110		101

Asset retirement obligations	61		41
Incentive plans	29		40
Net deferred hedge losses	68		—
South Texas Divestiture	62		75
Lease deferred tax assets	167		191
Other	47		47
Deferred tax assets	1,655		1,534
Deferred tax liabilities:
Oil and gas properties, principally due to differences in basis, depletion and the deduction of intangible drilling costs for tax purposes	(2,741)		(2,628)
Other property and equipment, principally due to the deduction of bonus depreciation for tax purposes	(196)		(189)
Net deferred hedge gains	—		(9)
South Texas Divestiture	(16)		(35)
Lease deferred tax liabilities	(43)		(61)
Convertible Notes	(23)		—


Other	(2)		(5)
Deferred tax liabilities	(3,021)		(2,927)
Net deferred tax liability	$	(1,366)	$	(1,393)

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(a)Net operating loss carryforwards as of December 31, 2020 consist of $5 billion of U.S. federal NOLs, which expire between 2032 and 2040. Additionally, the net operating loss carryforwards consist of $177 million of Colorado NOLs that begin to expire in 2027 and which has a fully offsetting valuation allowance.

(b)Credit carryforwards as of December 31, 2020, consist of $110 million of U.S. federal credits for research and experimental expenditures, which expire between 2032 and 2038.