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.

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Goodwill and Intangible Assets - Schedule of Goodwill (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 25,760us-gaap_Goodwill	$ 20,478us-gaap_Goodwill
Adjustment for the sale of OCTG business	(4,412)
Additions		5,282us-gaap_GoodwillAcquiredDuringPeriod
Fourth quarter impairment	(16,066)us-gaap_GoodwillImpairmentLoss
Goodwill, Ending Balance	5,282us-gaap_Goodwill	25,760us-gaap_Goodwill
Water Transmission [Member]
Goodwill [Line Items]
Goodwill, Ending Balance	5,300
Water Transmission [Member] \| Operating Segments [Member]
Goodwill [Line Items]
Additions		5,282
Goodwill, Ending Balance	5,282	5,282
Tubular Products [Member]
Goodwill [Line Items]
Fourth quarter impairment	(16,066)	0	0
Goodwill, Ending Balance	16,100
Tubular Products [Member] \| Operating Segments [Member]
Goodwill [Line Items]
Goodwill, Beginning Balance	20,478
Adjustment for the sale of OCTG business	(4,412)
Fourth quarter impairment	(16,066)
Goodwill, Ending Balance			$ 20,478