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v3.19.1

Goodwill - Key assumptions used in the determination of recoverable value (Details) | 12 Months Ended
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Dec. 31, 2018 | Dec. 31, 2017
Disclosure of significant unobservable inputs used in fair value measurement of assets [abstract] |  |
Period of projections | 5 years |
Electrometallurgy United States Segment |  |
Disclosure of significant unobservable inputs used in fair value measurement of assets [abstract] |  |
Weighted Average Cost of Capital | 11.00% | 10.50%
Long-Term Growth Rate | 2.00% | 1.50%
Normalized Tax Rate | 22.00% | 27.10%
Normalized Cash Free Net Working Capital | 21.00% | 21.00%
Electrometallurgy Canada Segment |  |
Disclosure of significant unobservable inputs used in fair value measurement of assets [abstract] |  |
Weighted Average Cost of Capital | 10.50% | 10.50%
Long-Term Growth Rate | 2.00% | 1.50%
Normalized Tax Rate | 26.50% | 26.50%
Normalized Cash Free Net Working Capital | 21.00% | 21.00%

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