Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Jan. 01, 2018
Summary of Significant Accounting Policies (Textual) [Abstract]
Maximum period in which contracts for the sale of grain to processors or other consumers extend	1 year
Marketing lease agreement term	5 years
Marketing balance payable		$ 3,300
Property subject to or available for leases statutory life minimum	40 years
Property subject to or available for leases statutory life maximum	50 years
Accrued compensation liability	$ 7,500	9,600
Decrease in retained earnings	(647,517)	(633,496)
Revenues under ASC 606 | ASC 606 Impact
Summary of Significant Accounting Policies (Textual) [Abstract]
Decrease in retained earnings	$ (7,778)
Revenues under ASC 606 | ASC 606 Impact | Rail Group
Summary of Significant Accounting Policies (Textual) [Abstract]
Decrease in retained earnings				$ 8,400
Net Assets | Revenues under ASC 606 | Rail Group
Summary of Significant Accounting Policies (Textual) [Abstract]
Increase in net assets				25,600
Financing Liabilities | Revenues under ASC 606 | Rail Group
Summary of Significant Accounting Policies (Textual) [Abstract]
Increase in financial liabilities and deferred tax liabilities				$ 34,000
Minimum
Summary of Significant Accounting Policies (Textual) [Abstract]
Intangible assets estimated useful life	3 years
Maximum
Summary of Significant Accounting Policies (Textual) [Abstract]
Intangible assets estimated useful life	10 years
Operating, administrative and general expenses
Summary of Significant Accounting Policies (Textual) [Abstract]
Advertising expense	$ 1,900	$ 2,500	$ 4,900
Barges | Minimum
Summary of Significant Accounting Policies (Textual) [Abstract]
Asset estimated average useful life	30 years
Barges | Maximum
Summary of Significant Accounting Policies (Textual) [Abstract]
Asset estimated average useful life	40 years
Land Improvements
Summary of Significant Accounting Policies (Textual) [Abstract]
Asset estimated average useful life	16 years
Leasehold Improvements | Minimum
Summary of Significant Accounting Policies (Textual) [Abstract]
Asset estimated average useful life	3 years
Leasehold Improvements | Maximum
Summary of Significant Accounting Policies (Textual) [Abstract]
Asset estimated average useful life	20 years
Buildings and Storage Facilities | Minimum
Summary of Significant Accounting Policies (Textual) [Abstract]
Asset estimated average useful life	10 years
Buildings and Storage Facilities | Maximum
Summary of Significant Accounting Policies (Textual) [Abstract]
Asset estimated average useful life	40 years
Machinery and Equipment | Minimum
Summary of Significant Accounting Policies (Textual) [Abstract]
Asset estimated average useful life	3 years
Machinery and Equipment | Maximum
Summary of Significant Accounting Policies (Textual) [Abstract]
Asset estimated average useful life	20 years