Property, Plant and Equipment, net (Details) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2015	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014
Property, plant and equipment, net
Document Period End Date		Sep. 30, 2015
Gross property, plant and equipment	$ 567.9	$ 567.9		$ 520.3
Less: Accumulated depreciation and amortization	257.6	257.6		260.9
Net property, plant and equipment	310.3	310.3		259.4
Loss on disposal of property, plant and equipment	0.5	1.7	$ 0.0
Net capitalized turnaround costs:
Beginning balance		16.7	22.7
Additions		33.1	0.3
Depreciation		(8.5)	(4.7)
Ending balance	41.3	41.3	$ 18.3
Land
Property, plant and equipment, net
Gross property, plant and equipment	1.6	1.6		1.6
Buildings and improvements
Property, plant and equipment, net
Gross property, plant and equipment	14.6	14.6		8.1
Machinery and equipment
Property, plant and equipment, net
Gross property, plant and equipment	539.4	539.4		401.4
Construction in progress
Property, plant and equipment, net
Gross property, plant and equipment	$ 12.3	$ 12.3		$ 109.2