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Restructuring and Other (Income) Charges, net - Narrative (Details) - USD ($) $ in Millions		12 Months Ended
	Oct. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations
Severance costs		$ 1.3	$ 6.3	$ 0.0
Other restructuring cost		2.4	4.3	0.0
Gain on sale of assets and businesses		0.0	0.0	11.5
Impairment of long-lived assets to be disposed of		0.0	30.6	$ 4.0
Subsidiaries
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations
Interest in subsidiary (as a percentage)				60.00%
Gain on sale of assets and businesses				$ 10.3
Performance Chemicals
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations
Asset impairment		0.3
Performance Materials
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations
Gain on sale of assets and businesses				$ 1.2
Employee related severance cost
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations
Severance costs		2.7
Employee related severance cost \| Performance Chemicals
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations
Severance costs		1.9
Employee related severance cost \| Performance Materials
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations
Severance costs		$ 0.8
Palmeira, Santa Catarina, Brazil, Performance Chemicals
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations
Severance costs	$ 1.8
Other restructuring cost			2.6
Asset impairment	$ 30.2
Duque De Caxias, Rio de Janeiro, Brazil, Performance Chemicals
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations
Severance costs			1.8
Other restructuring cost			1.7
Asset impairment			$ 0.1