Income Taxes (Tables)

12 Months Ended

Dec. 31, 2020

Components of Earnings Before Income Taxes and Noncontrolling Interests

Components of earnings before income taxes and noncontrolling interests are as follows (in thousands):

	Year Ended December 31,
	2020			2019			2018
United States	$	1,215,909		$	1,806,704		$	3,160,111
Foreign		(380,371	)		(23,897	)		69,280
	$	835,538		$	1,782,807		$	3,229,391

Provision for Income Taxes

The provision for income taxes consists of the following (in thousands):

	Year Ended December 31,
	2020			2019			2018
Current:
Federal	$	(177,159	)	$	241,074		$	633,868
State		(4,298	)		62,685			96,622
Foreign		18,131			8,981			14,800
Total current		(163,326	)		312,740			745,290
Deferred:
Federal		177,035			101,946			4,953
State		(25,500	)		8,013			6,847
Foreign		11,301			(10,802	)		(8,783	)
Total deferred		162,836			99,157			3,017
Total provision for income taxes	$	(490	)	$	411,897		$	748,307

Reconciliation of the Federal Statutory Tax Rate to Total Provisions

A reconciliation of the federal statutory tax rate (21%) to the total provision is as follows:

	Year Ended December 31,
	2020	2019	2018
Taxes computed at statutory rate	21.00%	21.00%	21.00%
State income taxes, net of federal income tax benefit	-3.36%	3.16%	2.52%
Federal research credit	-0.79%	-0.34%	-0.14%
Equity in losses of foreign joint venture	0.64%	0.19%	0.08%
Impairment on investment in foreign joint venture	11.20%	—	—
Tax loss on investment in foreign joint venture	-22.73%	—	—
Foreign rate differential	1.15%	—	-0.07%
Noncontrolling interests	-2.88%	-1.18%	-0.78%
Tax Reform Act	—	—	0.18%
CARES Act NOL carryback	-5.77%	—	—
Other, net	1.49%	0.27%	0.38%
Provision for income taxes	-0.06%	23.10%	23.17%

Deferred Tax Assets and Liabilities

Deferred tax assets and liabilities resulted from the following (in thousands):

	December 31,
	2020			2019
Deferred tax assets:
Accrued liabilities and reserves	$	171,998		$	146,658
Allowance for doubtful accounts		16,434			18,479
Inventory		62,755			79,363
Post-retirement benefits		12,714			10,288
Commodity hedges		4,033			5,164
Net operating loss carryforward		63,952			59,083
Tax credit carryforwards		187,267			164,132
Other deferred tax assets		10,674			8,508
Valuation allowance		(207,653	)		(192,295	)
Total deferred tax assets		322,174			299,380
Deferred tax liabilities:
Holdbacks and amounts not due under contracts		(14,051	)		(12,930	)
Intangibles		(177,061	)		(171,531	)
Property, plant and equipment		(680,688	)		(545,890	)
Book/Tax differences on debt modifications		(46,813	)		-
Total deferred tax liabilities		(918,613	)		(730,351	)
Total net deferred tax liabilities	$	(596,439	)	$	(430,971	)

Reconciliation of the Beginning and Ending Amounts of Unrecognized Tax Benefits

A reconciliation of the beginning and ending amounts of unrecognized tax benefits recorded in deferred credits and other liabilities in the consolidated balance sheets is as follows (in thousands):

	December 31,
	2020			2019			2018
Balance at beginning of year	$	50,920		$	48,605		$	48,845
Additions based on tax positions related to current year		4,138			9,272			16,424
Reductions based on tax positions related to current year		—			—			—
Additions based on tax positions related to prior years		223			2,106			199
Reductions based on tax positions related to prior years		—			(2,863	)		(8,198	)
Reductions due to settlements with taxing authorities		—			(1,514	)		(2,160	)
Reductions due to statute of limitations lapse		(7,316	)		(4,686	)		(6,505	)
Balance at end of year	$	47,965		$	50,920		$	48,605