Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2013	Mar. 31, 2012
Segment Information Report
Net sales	$ 140,597	$ 142,175
Gross profit	21,204	16,500
Operating income (loss)	14,820	9,179
Water Transmission [Member]
Segment Information Report
Net sales	78,613	58,431
Gross profit	19,870	9,699
Operating income (loss)	18,033	8,024
Tubular Products [Member]
Segment Information Report
Net sales	61,984	83,744
Gross profit	1,334	6,801
Operating income (loss)	666	6,196
Corporate [Member]
Segment Information Report
Operating income (loss)	$ (3,879)	$ (5,041)

Aggregate revenue less cost of goods and services sold or operating expenses directly attributable to the revenue generation activity.

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- Definition

The net result for the period of deducting operating expenses from operating revenues.

+ References

No definition available.

+ Details

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- Definition

Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=6880815&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 1

-Article 5

+ Details

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