Property, Plant and Equipment (Details Textual) - USD ($) $ in Millions	1 Months Ended	3 Months Ended
	Dec. 31, 2016	Mar. 31, 2017	Mar. 31, 2016
Property, Plant and Equipment [Line Items]
Depreciation expense		$ 12.1	$ 12.1
Depreciation expense on railcar assets leased to others		$ 4.7	$ 4.6
Retail
Property, Plant and Equipment [Line Items]
Impairment of long-lived assets	$ 6.0
Capitalized computer software, impairments	0.5
Plant Nutrient
Property, Plant and Equipment [Line Items]
Impairment of long-lived assets	$ 2.3