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

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 210.5-03.1,2)
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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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.

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- Definition

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

+ References

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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=63488584&loc=d3e20235-122688

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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=63488584&loc=d3e20235-122688

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Segment Information (Details) $ in Thousands	3 Months Ended				6 Months Ended	9 Months Ended
Segment Information (Details) $ in Thousands	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	Sep. 30, 2015 USD ($)	Jun. 30, 2016 USD ($)	Sep. 30, 2016 USD ($) segment	Sep. 30, 2015 USD ($)
Segment Reporting, Other Significant Reconciling Item [Line Items]
Number of reportable segments \| segment						3
Net sales:	$ 272,734			$ 304,994		$ 776,143	$ 758,780
Income from operations:	67,887	$ 68,843	$ 54,150	61,396	$ 122,993	190,880	135,430
Unallocated Corporate Expenses	(11,323)			(5,585)		(26,381)	(17,818)
Total income from operations	26,363	$ 28,416	$ 17,601	23,394	$ 46,017	72,380	43,565
Residential Products
Segment Reporting, Other Significant Reconciling Item [Line Items]
Net sales:	117,957			126,995		338,069	368,459
Income from operations:	19,407			15,879		52,363	39,922
Industrial and Infrastructure Products
Segment Reporting, Other Significant Reconciling Item [Line Items]
Net sales:	73,193			96,636		234,590	292,821
Income from operations:	1,913			8,083		11,429	15,445
Renewable Energy & Conservation
Segment Reporting, Other Significant Reconciling Item [Line Items]
Net sales:	82,008			81,649		204,648	98,733
Income from operations:	16,366			5,017		34,969	6,016
Intersegment Elimination
Segment Reporting, Other Significant Reconciling Item [Line Items]
Net sales:	(424)			(286)		(1,164)	(1,233)
Intersegment Elimination \| Industrial and Infrastructure Products
Segment Reporting, Other Significant Reconciling Item [Line Items]
Net sales:	$ 72,769			$ 96,350		$ 233,426	$ 291,588