Income Taxes (Tables)

12 Months Ended

Dec. 31, 2018

Income tax expense was as follows (in millions):

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



	Year Ended		Year Ended		Year Ended
	December 31, 2018		December 31, 2017		December 31, 2016
U.S. Federal statutory income tax rate	21.0	%	35.0	%	35.0	%
State income taxes, net of federal tax benefit	2.8		2.9		2.5
Tax law change	—		(116.0	)	—
Other, net	0.2		(0.5	)	(0.2	)
Effective tax rate	24.0	%	(78.6	)%	37.3	%

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



	December 31, 2018			December 31, 2017
Deferred tax liabilities:
Property and equipment	$	(13,860	)	$	(13,583	)
Other	(346		)	(391		)
Total deferred tax liabilities	(14,206		)	(13,974		)
Deferred tax assets:
Compensation and benefits	165			112
Casualty and Environmental	122			159
Long-term debt fair value adjustment under acquisition method accounting	27			32
Intangible assets and liabilities	16			32
Pension and retiree health and welfare benefits	16			16
Other	65			171
Total deferred tax assets	411			522
Net deferred tax liability	$	(13,795	)	$	(13,452	)

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



	Year Ended			Year Ended			Year Ended
	December 31, 2018			December 31, 2017			December 31, 2016
Beginning balance	$	57		$	62		$	69
Additions for tax positions related to current year	2			7			4
Additions (reductions) for tax positions taken in prior years	5			(1		)	(1		)
Additions (reductions) for tax positions as a result of:
Settlements	—			—			1
Lapse of statute of limitations	(14		)	(11		)	(11		)
Ending balance	$	50		$	57		$	62