Income Taxes (Details 3) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Deferred tax liabilities:
Property, plant and equipment and Rail Group assets leased to others	$ (179,250)	$ (170,588)
Equity method investments	(45,244)	(45,673)
Other	(22,286)	(22,261)
Deferred tax liabilities	(246,780)	(238,522)
Deferred tax assets:
Employee benefits	25,403	27,160
Accounts and notes receivable	2,964	2,611
Inventory	9,979	11,918
Income Tax Credits and Adjustments	7,150
Effective Income Tax Rate Reconciliation, Tax Credit, Foreign, Amount	1,100	0
Net operating loss carryforwards	3,322	4,542
Other	16,224	13,583
Total deferred tax assets	65,042	59,814
Valuation allowance	(310)	(593)
Net deferred tax assets	64,732	59,221
Net deferred tax liabilities	$ (182,048)	$ (179,301)