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Rationalizations (Narrative) (Details) $ in Millions		3 Months Ended	9 Months Ended
Rationalizations (Narrative) (Details) $ in Millions	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