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Goodwill and Related Intangible Assets (Schedule of Changes in Carrying Amount of Goodwill) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
Goodwill [Roll Forward] |  |  |
Balance at | $ 292,390 | $ 236,044 |
Acquired goodwill | 12,283 | 57,180 |
Impairment | (929) |  | $ (104,565)
Foreign currency translation | 288 | (834) |
Balance at | 304,032 | 292,390 | 236,044
Residential Products |  |  |
Goodwill [Roll Forward] |  |  |
Balance at | 181,285 | 181,285 |
Acquired goodwill | 0 | 0 |
Impairment | 0 |  |
Foreign currency translation | 0 | 0 |
Balance at | 181,285 | 181,285 | 181,285
Industrial and Infrastructure Products |  |  |
Goodwill [Roll Forward] |  |  |
Balance at | 53,704 | 54,759 |
Acquired goodwill | 0 | 0 |
Impairment | 0 |  |
Foreign currency translation | 180 | (1,055) |
Balance at | 53,884 | 53,704 | 54,759
Renewable Energy & Conservation |  |  |
Goodwill [Roll Forward] |  |  |
Balance at | 57,401 | 0 |
Acquired goodwill | 12,283 | 57,180 |
Impairment | (929) |  |
Foreign currency translation | 108 | 221 |
Balance at | $ 68,863 | $ 57,401 | $ 0

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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=64834752&loc=SL49117168-202975 + Details
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- Definition Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267 + Details
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