Goodwill and Other Intangible Assets (Schedule of Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 57,781us-gaap_Goodwill	$ 41,237us-gaap_Goodwill
Acquisitions	25,209us-gaap_GoodwillAcquiredDuringPeriod	16,544us-gaap_GoodwillAcquiredDuringPeriod
Foreign currency translation impact	(41)us-gaap_GoodwillTranslationAdjustments
Goodwill, Ending Balance	82,949us-gaap_Goodwill	57,781us-gaap_Goodwill
Rail Products Segment [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	38,026	38,026
Acquisitions	971	0
Foreign currency translation impact	(41)
Goodwill, Ending Balance	38,956	38,026
Construction Products Segment [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	3,211	3,211
Acquisitions	1,936	0
Foreign currency translation impact	0
Goodwill, Ending Balance	5,147	3,211
Tubular Products Segments [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	16,544	0
Acquisitions	22,302	16,544
Foreign currency translation impact	0
Goodwill, Ending Balance	$ 38,846	$ 16,544

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://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

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