Property, Plant and Equipment, Net (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Property, plant and equipment, net
Gross property, plant and equipment	$ 627.7	$ 602.3
Less: Accumulated depreciation and amortization	337.5	301.0
Net property, plant and equipment	290.2	301.3
Construction in Progress Expenditures Incurred but Not yet Paid	0.6	1.8	$ (2.2)
Losses on Disposition of Property Plant Equipment	0.0	(0.1)	(2.0)
Net capitalized turnaround costs:
Beginning balance	26.6	37.8	16.7
Additions	2.3	4.9	33.6
Depreciation	(14.2)	(16.1)	(12.5)
Ending balance	14.7	26.6	$ 37.8
Land
Property, plant and equipment, net
Gross property, plant and equipment	1.4	1.4
Buildings and improvements
Property, plant and equipment, net
Gross property, plant and equipment	16.9	16.7
Machinery and equipment
Property, plant and equipment, net
Gross property, plant and equipment	568.3	562.3
Construction in progress
Property, plant and equipment, net
Gross property, plant and equipment	$ 41.1	$ 21.9