Supplemental Cash Flow Information Footnote (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Cash Flow Supplemental Disclosures [Line Items]
Transition tax on foreign earnings, current	$ 28.4
Transition tax on foreign earnings		$ 394.9
Foreign currency exchange rate losses	10.5	11.1	$ 40.8
Polyolefin Catalysts
Cash Flow Supplemental Disclosures [Line Items]
Income taxes paid from gain on sale	$ 41.0
Chemetall Surface Treatment
Cash Flow Supplemental Disclosures [Line Items]
Income taxes paid from gain on sale		$ 257.0