Property, Plant and Equipment and Railcars on Leases, net (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Components of property, plant and equipment
Property, plant and equipment, net	$ 175,784	$ 176,311
Operations / Corporate: [Member]
Components of property, plant and equipment
Property, plant and equipment, gross	409,618	407,496
Less accumulated depreciation	(233,834)	(231,185)
Property, plant and equipment, net	175,784	176,311
Railcar Leasing [Member]
Components of property, plant and equipment
Property, plant and equipment, gross	926,909	906,786
Less accumulated depreciation	(65,421)	(58,069)
Property, plant and equipment, net	861,488	848,717
Buildings [Member] | Operations / Corporate: [Member]
Components of property, plant and equipment
Property, plant and equipment, gross	177,736	167,537
Machinery and equipment [Member] | Operations / Corporate: [Member]
Components of property, plant and equipment
Property, plant and equipment, gross	221,571	219,488
Land [Member] | Operations / Corporate: [Member]
Components of property, plant and equipment
Property, plant and equipment, gross	3,687	3,687
Construction in process [Member] | Operations / Corporate: [Member]
Components of property, plant and equipment
Property, plant and equipment, gross	$ 6,624	$ 16,784