Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(12))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(11))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

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The net result for the period of deducting operating expenses from operating revenues.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Operating Segment and Sales and Credit Concentrations (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2017 USD ($) segment	Mar. 31, 2016 USD ($)	Dec. 31, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of Reportable Segments \| segment	3
Total revenues	$ 114,681	$ 176,180
Earnings from operations	21,915	40,697
Total Assets	1,459,637		$ 1,456,250
Corporate/Eliminations [Member]
Segment Reporting Information [Line Items]
Total Assets	(152,936)		(112,257)
Manufacturing [Member]
Segment Reporting Information [Line Items]
Total revenues	120,830	147,423
Earnings from operations	9,151	22,686
Total Assets	237,705		256,622
Railcar Leasing [Member]
Segment Reporting Information [Line Items]
Total revenues	33,835	32,768
Earnings from operations	18,810	19,675
Total Assets	1,314,257		1,254,824
Railcar Services [Member]
Segment Reporting Information [Line Items]
Total revenues	20,452	20,579
Earnings from operations	1,716	3,508
Total Assets	60,611		$ 57,061
Corporate Segment [Member]
Segment Reporting Information [Line Items]
Earnings from operations	(4,272)	(4,508)
Eliminations [Member]
Segment Reporting Information [Line Items]
Total revenues	(60,436)	(24,590)
Earnings from operations	(3,490)	(664)
Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenues	114,681	176,180
Operating Segments [Member] \| Manufacturing [Member]
Segment Reporting Information [Line Items]
Total revenues	60,726	123,792
Operating Segments [Member] \| Railcar Leasing [Member]
Segment Reporting Information [Line Items]
Total revenues	33,835	32,768
Operating Segments [Member] \| Railcar Services [Member]
Segment Reporting Information [Line Items]
Total revenues	20,120	19,620
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Total revenues	0	0
Intersegment Eliminations [Member] \| Manufacturing [Member]
Segment Reporting Information [Line Items]
Total revenues	60,104	23,631
Intersegment Eliminations [Member] \| Railcar Leasing [Member]
Segment Reporting Information [Line Items]
Total revenues	0	0
Intersegment Eliminations [Member] \| Railcar Services [Member]
Segment Reporting Information [Line Items]
Total revenues	332	959
Intersegment Eliminations [Member] \| Eliminations [Member]
Segment Reporting Information [Line Items]
Total revenues	$ (60,436)	$ (24,590)