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Goodwill and Related Intangible Assets (Narrative) (Details) $ in Thousands | 1 Months Ended | 9 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Oct. 31, 2015 reporting_unit | Sep. 30, 2013 USD ($) | Dec. 31, 2015 USD ($) reporting_unit | Dec. 31, 2014 USD ($) reporting_unit | Dec. 31, 2013 USD ($) | Oct. 31, 2014
Goodwill [Line Items] |  |  |  |  |  |
Accumulated impairment losses | $ |  |  | $ 255,530 | $ 255,530 |  |
Goodwill impairment | $ |  |  |  | $ (104,565) | $ (104,565) |
Number of reporting units tested | 11 |  |  | 4 |  |
Number of reporting units |  |  | 12 |  |  |
Industrial and Infrastructure Products |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |
Number of reporting units tested |  |  |  | 1 |  |
Number of reporting units |  |  |  | 2 |  |
Residential Products |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |
Number of reporting units |  |  |  | 2 |  |
Industrial Specialty Products |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |
Goodwill impairment | $ |  | $ (21,040) |  |  |  |
Maximum |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |
WACC | 13.10% |  |  |  |  | 13.60%
Minimum |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |
WACC | 11.30% |  |  |  |  | 12.90%

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