Goodwill and Other Intangible Assets (Schedule of Goodwill) (Details) $ in Thousands	3 Months Ended
Mar. 31, 2019 USD ($)
Goodwill
Goodwill, beginning balance	$ 19,258
Foreign currency translation impact	164
Goodwill, ending balance	19,422
Rail Products and Services
Goodwill
Goodwill, beginning balance	14,111
Foreign currency translation impact	164
Goodwill, ending balance	14,275
Construction Products
Goodwill
Goodwill, beginning balance	5,147
Foreign currency translation impact	0
Goodwill, ending balance	5,147
Tubular and Energy Services
Goodwill
Goodwill, beginning balance	0
Foreign currency translation impact	0
Goodwill, ending balance	$ 0

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=99380562&loc=d3e13770-109266

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Amount of foreign currency translation gain (loss) which increases (decreases) an asset representing future economic benefits from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=108376223&loc=d3e13816-109267

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