Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012 Segment	Sep. 30, 2011
Segment Information Report
Net sales	$ 115,099	$ 139,265	$ 388,315	$ 394,524
Total Gross profit	11,600	16,514	41,677	47,953
Total Operating income (Loss)	4,029	10,047	20,178	28,594
Segment Information (Textual) [Abstract]
Number of reportable segments			2
Water Transmission [Member]
Segment Information Report
Net sales	63,487	76,953	180,968	210,057
Total Gross profit	9,681	13,345	27,529	34,770
Total Operating income (Loss)	6,969	10,747	21,123	28,150
Tubular Goods [Member]
Segment Information Report
Net sales	51,612	62,312	207,347	184,467
Total Gross profit	1,919	3,169	14,148	13,183
Total Operating income (Loss)	1,134	2,349	11,981	10,502
Corporate [Member]
Segment Information Report
Total Operating income (Loss)	$ (4,074)	$ (3,049)	$ (12,926)	$ (10,058)

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

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

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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.

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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

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