Income Taxes (Tables)

12 Months Ended

Dec. 31, 2016

Income Tax Disclosure [Abstract]

Schedule of Income before Income Tax, Domestic and Foreign [Table Text Block]

The components of income before income taxes for the years ended December 31, 2016, 2015 and 2014 were as follows (dollars in thousands):

	2016			2015		2014
United States	$	273,361		$	236,613	$	276,594
Foreign	(57,870		)	64,318		91,519
Total	$	215,491		$	300,931	$	368,113

Schedule of Components of Income Tax Expense (Benefit) [Table Text Block]

The components of the provision for income taxes for the years ended December 31, 2016, 2015 and 2014 were as follows (dollars in thousands):

	2016			2015			2014
United States:
Current
Federal	$	20,877		$	12,003		$	15,647
State	11,284			8,181			7,134
Deferred
Federal	43,820			41,975			49,799
State	2,263			5,383			8,727
	78,244			67,542			81,307
Foreign:
Current	3,289			11,031			17,591
Deferred	(7,138		)	(2,679		)	8,209
	(3,849		)	8,352			25,800
Total	$	74,395		$	75,894		$	107,107

Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]

The following is a summary of the effective income tax rate reconciliation for the years ended December 31, 2016, 2015 and 2014:

	2016		2015		2014
Tax provision at statutory rate	35.0	%	35.0	%	35.0	%
Effect of foreign operations	4.3	%	(3.8	)%	(1.7	)%
Foreign valuation allowance	2.9	%	2.1	%	—	%
Foreign goodwill impairment	2.4	%	—	%	—	%
Effect of foreign tax rate change	(2.0	)%	(3.3	)%	—	%
State income taxes, net of federal income tax benefit	4.1	%	3.0	%	2.8	%
Benefit of track maintenance credit	(13.4	)%	(9.1	)%	(7.3	)%
Other, net	1.2	%	1.3	%	0.3	%
Effective income tax rate	34.5	%	25.2	%	29.1	%

Schedule of Deferred Tax Assets and Liabilities [Table Text Block]

The components of net deferred income taxes as of December 31, 2016 and 2015 were as follows (dollars in thousands):

	2016			2015
Deferred income tax assets:
Track maintenance credit carryforward	$	217,054		$	237,411
Net operating loss carryforwards	23,168			20,810
Accruals and reserves not deducted for tax purposes until paid	15,131			14,896
Stock-based compensation	10,089			9,253
Deferred revenue	6,311			5,736
Deferred compensation	3,891			3,454
Nonshareholder contributions	1,978			2,150
Interest rate swaps	—			4,223
Alternative minimum tax credit carryforward	1,592			1,592
Pension and postretirement benefits	18,693			15,411
Other	2,072			752
	299,979			315,688
Valuation allowance	(24,075		)	(19,315		)
Deferred income tax liabilities:
Interest rate swaps	(4,579		)	—
Property and equipment basis difference	(1,012,109		)	(967,998		)
Intangible assets basis difference	(418,398		)	(302,903		)
Other	(368		)	(6,338		)
Net deferred tax liabilities	$	(1,159,550	)	$	(980,866	)

Summary of Valuation Allowance [Table Text Block]

A reconciliation of the beginning and ending amount of the Company's valuation allowance is as follows (dollars in thousands):

	2016			2015
Balance at beginning of year	$	19,315		$	14,793
(Decrease)/increase for state net operating losses	(1,476		)	89
Increase for foreign net operating losses and impairments	6,236			6,397
Decrease for certain other deferred income tax assets	—			(1,964		)
Balance at end of year	$	24,075		$	19,315

Summary of Income Tax Contingencies [Table Text Block]

A reconciliation of the beginning and ending amount of the Company's liability for uncertain tax positions is as follows (dollars in thousands):

	2016			2015			2014
Balance at beginning of year	$	4,197		$	4,324		$	3,155
Increase for tax positions related to prior years	3,970			—			1,169
Decrease for tax positions related to prior years	(1,169		)	—			—
Increase/(decrease) for effects of foreign exchange rates	127			(127		)	—
Balance at end of year	$	7,125		$	4,197		$	4,324

Summary of Income Tax Examinations [Table Text Block]

As of December 31, 2016, the following tax years remain open to examination by the major taxing jurisdictions to which the Company is subject:

	Open Tax Years
	From		To
United States	2002	-	2016
Australia	2010	-	2016
Belgium	2014	-	2016
Canada	2009	-	2016
Germany	2010	-	2016
Mexico	2008	-	2016
Netherlands	2011	-	2016
Poland	2011	-	2016
Saudi Arabia	2015	-	2016
U.K.	2010	-	2016