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Rationalizations (Narrative) (Details) $ in Millions |  | 3 Months Ended | 9 Months Ended
--- | --- | --- | ---
Mar. 02, 2015 USD ($) employee | Jun. 30, 2015 USD ($) | Sep. 30, 2016 USD ($)
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring Reserve |  |  | $ 0.2
2015 Advanced Graphite Materials Rationalization |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring Reserve |  |  | 0.6
Expected number of positions eliminated (employees) | employee | 85 |  |
Expected cost | $ 10.0 |  |
2015 Advanced Graphite Materials Rationalization | Scenario, Forecast |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Expected cash outlay |  |  | 8.0
2015 Advanced Graphite Materials Rationalization | Successor |  |  |
Restructuring Cost and Reserve [Line Items] |  |  |
Restructuring Costs |  | $ 0.8 | $ 1.3

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