The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Goodwill and Other Intangible Assets (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Sep. 30, 2015	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Goodwill, Impairment Loss	$ 80,337	$ 80,337	$ 0	$ 0
Goodwill, Impairment Loss, Net of Tax	$ 63,887	63,887
Impairment of Long-Lived Assets Held-for-use		0	0	0
Finite-Lived Intangible Assets, Gross		158,740	95,771
Amortization of Intangible Assets		$ 12,245	4,695	$ 3,112
Maximum [Member]
Finite-Lived Intangible Asset, Useful Life		25 years
Minimum [Member]
Finite-Lived Intangible Asset, Useful Life		5 years
Weighted Average [Member]
Finite-Lived Intangible Asset, Useful Life		14 years
Rail Products and Services [Member]
Goodwill, Impairment Loss		$ 0
Finite-Lived Intangible Assets, Gross		59,226	44,781
Construction Products [Member]
Goodwill, Impairment Loss		0
Finite-Lived Intangible Assets, Gross		1,348	3,178
Tubular and Energy Services [Member]
Goodwill, Impairment Loss		80,337
Finite-Lived Intangible Assets, Gross		98,166	$ 47,812
Inspection Oilfield Services (IOS) [Member]
Goodwill, Impairment Loss		69,908
Chemtec Energy Services, LLC [Member]
Goodwill, Impairment Loss		$ 10,429