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Goodwill and Related Intangible Assets (Schedule of Changes in Carrying Amount of Goodwill) (Details) - USD ($) $ in Thousands | 6 Months Ended |
--- | --- | ---
Jun. 30, 2017 | Dec. 31, 2016
Goodwill [Roll Forward] |  |
Balance at | $ 304,032 |
Acquired goodwill | 16,931 |
Adjustments to prior year acquisitions | (832) |
Foreign currency translation | 717 |
Balance at | 320,848 |
Accumulated impairment losses | 235,419 | $ 234,490
Residential Products |  |
Goodwill [Roll Forward] |  |
Balance at | 181,285 |
Acquired goodwill | 16,931 |
Adjustments to prior year acquisitions | 0 |
Foreign currency translation | 0 |
Balance at | 198,216 |
Industrial and Infrastructure Products |  |
Goodwill [Roll Forward] |  |
Balance at | 53,884 |
Acquired goodwill | 0 |
Adjustments to prior year acquisitions | 0 |
Foreign currency translation | 197 |
Balance at | 54,081 |
Renewable Energy & Conservation |  |
Goodwill [Roll Forward] |  |
Balance at | 68,863 |
Acquired goodwill | 0 |
Adjustments to prior year acquisitions | (832) |
Foreign currency translation | 520 |
Balance at | $ 68,551 |

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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=77989000&loc=SL49117168-202975 + Details
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