Income Taxes (Tables)

12 Months Ended

Dec. 31, 2020

Summary of Provision for Income Taxes from Continuing Operations

The following table summarizes our provision for income taxes for the periods presented:


	Year Ended December 31,
	2020		2019		2018
Current income taxes (benefit)
Federal	$	(1,236)	$	(1,236)	$	(2,471)
State	357		—		—
	(879)		(1,236)		(2,471)
Deferred income taxes (benefit)
Federal	1,236		1,236		2,471
State	(2,660)		2,137		523
	(1,424)		3,373		2,994
	$	(2,303)	$	2,137	$	523

Income Taxes Reconciliation

The following table reconciles the difference between the income tax expense (benefit) computed by applying the statutory tax rate to our income (loss) before income taxes and our reported income tax expense (benefit) for the periods presented:


	Year Ended December 31,
	2020				2019				2018
Computed at federal statutory rate	$	(65,701)	(21.0)	%	$	15,272	21.0	%	$	47,315	21.0	%
State income taxes, net of federal income tax benefit	(1,856)		(0.6)	%	1,494		2.1	%	1,743		0.8	%
Change in valuation allowance	64,062		20.5	%	(14,240)		(19.6)	%	(48,820)		(21.7)	%



Other, net	1,192		0.4	%	(389)		(0.5)	%	285		0.1	%
	$	(2,303)	(0.7)	%	$	2,137	3.0	%	$	523	0.2	%

Summary of Principal Components of Net Deferred Income Tax Liability

The following table summarizes the principal components of our deferred income tax assets and liabilities as of the dates presented:


	December 31,
	2020		2019
Deferred tax assets:
Net operating loss (“NOL”) carryforwards	$	180,531	$	175,221
Alternative minimum tax (“AMT”) credit carryforwards	—		1,236

Asset retirement obligations	1,188		1,073
Pension and postretirement benefits	301		340
Share-based compensation	467		880
Fair value of derivative instruments	2,737		4,191
Interest expense limitation	—		11,463
ROU assets	564		—
Other	1,484		2,441
	187,272		196,845
Less: Valuation allowance	(179,006)		(114,939)
Total net deferred tax assets	8,266		81,906
Deferred tax liabilities:
Property and equipment	7,728		83,330
ROU obligations	538		—
Total deferred tax liabilities	8,266		83,330
Net deferred tax liabilities	$	—	$	(1,424)