Segment Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
Mar. 31, 2015 segment	Mar. 31, 2014
Segment Reporting, Other Significant Reconciling Item [Line Items]
Number of reportable segments	2us-gaap_NumberOfReportableSegments
Net sales:	$ 200,615us-gaap_Revenues	$ 191,032us-gaap_Revenues
Income (loss) from operations:	29,915us-gaap_GrossProfit	29,864us-gaap_GrossProfit
Unallocated Corporate Expenses	(5,169)us-gaap_OtherCostAndExpenseOperating	(4,868)us-gaap_OtherCostAndExpenseOperating
Total income (loss) from operations	8,970us-gaap_OperatingIncomeLoss	333us-gaap_OperatingIncomeLoss
Residential Products
Segment Reporting, Other Significant Reconciling Item [Line Items]
Net sales:	106,795	86,983
Income (loss) from operations:	12,133	2,093
Industrial and Infrastructure Products
Segment Reporting, Other Significant Reconciling Item [Line Items]
Net sales:	94,285	104,346
Income (loss) from operations:	2,006	3,108
Intersegment Sales
Segment Reporting, Other Significant Reconciling Item [Line Items]
Net sales:	(465)	(297)
Intersegment Elimination \| Industrial and Infrastructure Products
Segment Reporting, Other Significant Reconciling Item [Line Items]
Net sales:	$ 93,820	$ 104,049

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

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- Definition

Number of segments reported by the entity. A reportable segment is a component of an entity for which there is an accounting requirement to report separate financial information on that component in the entity's financial statements.

+ References

No definition available.

+ Details

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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

The total amount of other operating cost and expense items that are associated with the entity's normal revenue producing operation.

+ 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 210.5-03.3)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 3

-Article 5

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ 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=26872669&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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