
	Year Ended December 31,
(in thousands)	2020		2019		2018
United States operations	$	138,426	$	(456,403)	$	106,222
Foreign and U.S. territory operations	35,853		30,569		26,391
Total	$	174,279	$	(425,834)	$	132,613


	Year Ended December 31,
(in thousands)	2020		2019		2018
Current (benefit) expense:
Federal	$	(36,159)	$	(2,884)	$	21,055
State	(1,282)		3,585		8,676
Foreign and U.S. territories	11,130		5,299		5,550
Total current (benefit) expense:	(26,311)		6,000		35,281

Deferred expense (benefit):
Federal	38,667		(43,579)		(1,773)
State	10,608		(27,566)		1,278
Foreign and U.S. territories	(1,022)		(464)		46
Total deferred expense (benefit):	48,253		(71,609)		(449)
Total expense (benefit):	$	21,942	$	(65,609)	$	34,832


	Year Ended December 31,
	2020				2019				2018
(dollars in thousands)	Amount		Rate		Amount		Rate		Amount		Rate
Federal income tax expense (benefit) at statutory tax rate	$	36,599	21.0	%	$	(89,425)	21.0	%	$	27,849	21.0	%
State income taxes, net of federal tax benefit	8,518		4.9		(18,442)		4.3		9,011		6.8
Stock based compensation	3,185		1.8		1,706		(0.4)		—		—
Impact of federal tax law changes	(14,476)		(8.3)		—		—		211		0.2
Officers' compensation	2,486		1.4		2,938		(0.7)		3,078		2.3
Goodwill impairment	—		—		43,990		(10.3)		—		—
Noncontrolling interests	(9,799)		(5.6)		(6,064)		1.4		(3,232)		(2.4)
Federal R&D credits	(3,007)		(1.7)		(3,998)		0.9		(2,658)		(2.0)
Reversal of reserve for uncertain tax positions due to statute expirations	(489)		(0.3)		(773)		0.2		(1,958)		(1.5)
Foreign tax rate differences	1,491		0.9		4,940		(1.2)		(19)		—
Other	(2,566)		(1.5)		(481)		0.2		2,550		1.9
Income tax expense (benefit)	$	21,942	12.6	%	$	(65,609)	15.4	%	$	34,832	26.3	%

The Company's provision for income taxes and effective tax rate for the year ended December 31, 2020 was significantly impacted by a change in tax law. On March 27, 2020, the Coronavirus Aid, Relief, and Economic Security Act (the “CARES Act”) was signed into law. A major provision of the CARES Act allows net operating losses from the 2018, 2019 and 2020 tax years to be carried back up to five years. As a result, for the year ended December 31, 2020, the Company was able to recognize tax benefits substantially in excess of the current federal statutory rate of 21% due to the effects of carrying back its net operating loss arising in 2019 to tax years in which the federal statutory rate was 35%.

The Company’s provision for income taxes and effective tax rate for the year ended December 31, 2019 was significantly impacted by the goodwill impairment charge discussed in Note 6. Of the total goodwill impairment charge of $379.9 million, approximately $209.5 million pertained to goodwill that was not tax deductible and yielded permanent differences between book income and taxable income. For the year ended December 31, 2019, the Company recognized U.S. federal and state tax benefits totaling $49.4 million as a result of the impairment charge.


	As of December 31,
(in thousands)	2020		2019
Deferred tax assets:
Timing of expense recognition	$	24,470	$	44,761
Net operating losses	19,968		23,711
Goodwill	19,315		26,658
Other, net	10,155		17,098
Deferred tax assets	73,908		112,228
Valuation allowance	—		(2,212)
Net deferred tax assets	73,908		110,016

Deferred tax liabilities:
Intangible assets, due primarily to purchase accounting	(15,212)		(15,309)
Fixed assets	(76,567)		(75,461)
Construction contract accounting	(9,769)		(13,464)
Joint ventures	(41,669)		(24,331)
Other	(11,962)		(16,567)
Deferred tax liabilities	(155,179)		(145,132)

Net deferred tax liabilities	$	(81,271)	$	(35,116)

As of December 31, 2020, the Company had net operating loss carryforwards for income tax purposes in various states totaling $196.5 million with expiration dates ranging from 2022 to 2039, and no net operating loss carryforwards for federal income tax purposes. As of December 31, 2019, the Company had federal and various state net operating loss carryforwards for income tax purposes of $29.3 million and $184.8 million, respectively. As of December 31, 2020, the Company had federal and state credit carryforwards of approximately $1.4 million and $2.0 million, respectively. As of December 31, 2019, the Company had federal and state credit carryforwards of approximately $6.0 million and $1.2 million, respectively.

The Company’s policy is to record interest and penalties on unrecognized tax benefits as an element of income tax expense. The cumulative amounts related to interest and penalties are added to the total unrecognized tax liabilities on the balance sheet. The total amount of gross unrecognized tax benefits as of December 31, 2020 that, if recognized, would affect the effective tax rate is $8.7 million. The Company does not expect any significant release of unrecognized tax benefits within the next twelve months.

The Company accounts for its uncertain tax positions in accordance with GAAP. The following is a reconciliation of the beginning and ending amounts of these unrecognized tax benefits for the three years ended December 31, 2020:


	As of December 31,
(in thousands)	2020		2019		2018
Beginning balance	$	5,682	$	4,998	$	6,495
Change in tax positions of prior years	2,286		351		(302)
Change in tax positions of current year	1,202		1,106		763
Reduction in tax positions for statute expirations	(489)		(773)		(1,958)
Ending Balance	$	8,681	$	5,682	$	4,998

The Company conducts business internationally and, as a result, one or more of its subsidiaries files income tax returns in U.S. federal, U.S. state and certain foreign jurisdictions. Accordingly, in the normal course of business, the Company is subject to examination by taxing authorities principally throughout the United States, Guam and Canada. The Company's open tax years for a U.S. federal income tax audit are for fiscal years 2017 and later, although there is currently no audit being conducted by the Internal Revenue Service. The Company has various years open to audit in a number of state and local jurisdictions and is currently under audit by certain state taxing authorities.