Income Taxes (Tables)

12 Months Ended

Dec. 31, 2019

(benefit) was as follows (in millions):

Reconciliation of the U.S. federal statutory income tax rate to the effective tax rate was as follows:



	Years ended December 31,
	2019		2018		2017
U.S. Federal statutory income tax rate	21.0	%	21.0	%	35.0	%
State income taxes, net of federal tax benefit	3.4		2.8		2.9
Tax law change	—		—		(116.0	)
Other, net	—		0.2		(0.5	)
Effective tax rate	24.4	%	24.0	%	(78.6	)%

The components of deferred tax assets and liabilities were as follows (in millions):



	December 31, 2019			December 31, 2018
Deferred tax liabilities:
Property and equipment	$	(14,313	)	$	(13,860	)
Operating lease right-of-use assets	(492		)	—
Other	(524		)	(346		)
Total deferred tax liabilities	(15,329		)	(14,206		)
Deferred tax assets:
Operating lease liabilities	475			—
Compensation and benefits	158			165
Casualty and environmental	114			122
Other	229			124
Total deferred tax assets	976			411
Net deferred tax liability	$	(14,353	)	$	(13,795	)

A reconciliation of the beginning and ending amount of unrecognized tax benefits is as follows (in millions):



	Years ended December 31,
	2019			2018			2017
Beginning balance	$	50		$	57		$	62
Additions for tax positions related to current year	8			2			7
Additions (reductions) for tax positions taken in prior years	(6		)	5			(1		)
Additions (reductions) for tax positions as a result of:
Lapse of statute of limitations	(6		)	(14		)	(11		)
Ending balance	$	46		$	50		$	57