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Goodwill and Related Intangible Assets (Schedule of Goodwill Impairment Tests) (Details) | Dec. 31, 2016 | Oct. 31, 2015 | Oct. 31, 2014
--- | --- | --- | ---
Minimum |  |  |
Goodwill [Line Items] |  |  |
WACC |  | 12.40% | 11.30%
Maximum |  |  |
Goodwill [Line Items] |  |  |
WACC |  | 13.00% | 13.10%
Renewable Energy & Conservation | Greenhouse |  |  |
Goodwill [Line Items] |  |  |
WACC | 15.10% |  |
Renewable Energy & Conservation | Solar |  |  |
Goodwill [Line Items] |  |  |
WACC | 16.10% |  |

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