Goodwill and Other Intangible Assets (Schedule of Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 82,949us-gaap_Goodwill
Acquisitions	132,491us-gaap_GoodwillAcquiredDuringPeriod
Foreign currency translation impact	(310)us-gaap_GoodwillTranslationAdjustments
Goodwill, Ending Balance	215,130us-gaap_Goodwill
Rail Products and Services Segment [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	38,956
Acquisitions	9,079
Foreign currency translation impact	(310)
Goodwill, Ending Balance	47,725
Construction Products Segment [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	5,147
Acquisitions	0
Foreign currency translation impact	0
Goodwill, Ending Balance	5,147
Tubular and Energy Services Segments [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	38,846
Acquisitions	123,412
Foreign currency translation impact	0
Goodwill, Ending Balance	$ 162,258

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=14024403&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

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-Section 45

-Paragraph 1

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 20

-Section 50

-Paragraph 1

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Amount of increase (decrease) from foreign currency translation adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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