Stockholders' Equity - Reclassification out of accumulated other comprehensive income (Details) - USD ($) $ in Millions	3 Months Ended						9 Months Ended
	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Sep. 30, 2017	Sep. 30, 2016
Schedule of Reclassifications out of Accumulated Comprehensive Income (Loss) [Line Items]
Cost of sales	$ (326.9)			$ (309.0)			$ (899.1)	$ (1,027.1)
Interest Expense	(9.6)			(10.0)			(29.4)	(29.6)
Income (loss) from continuing operations before taxes	(3.4)			(144.2)			(34.9)	(233.5)
Tax expense	13.1			5.3			9.3	(103.1)
Net income (loss)				(140.7)				(342.4)
Reclassification out of Accumulated Other Comprehensive Income
Schedule of Reclassifications out of Accumulated Comprehensive Income (Loss) [Line Items]
Net of Tax	2.3			(1.3)			0.9	(7.9)
Gains and Losses on Cash Flow Hedges
Schedule of Reclassifications out of Accumulated Comprehensive Income (Loss) [Line Items]
Net of Tax		$ (0.1)	$ (0.2)		$ 0.1	$ (4.3)		(0.2)
Gains and Losses on Cash Flow Hedges | Reclassification out of Accumulated Other Comprehensive Income
Schedule of Reclassifications out of Accumulated Comprehensive Income (Loss) [Line Items]
Income (loss) from continuing operations before taxes				(0.2)			(0.3)	(5.5)
Tax expense								1.1
Net income (loss)				(0.2)			(0.3)	(4.4)
Gains and Losses on Cash Flow Hedges | Reclassification out of Accumulated Other Comprehensive Income | Commodity contracts
Schedule of Reclassifications out of Accumulated Comprehensive Income (Loss) [Line Items]
Cost of sales				(0.2)			(0.3)	(1.2)
Gains and Losses on Cash Flow Hedges | Reclassification out of Accumulated Other Comprehensive Income | Interest rate swap contracts
Schedule of Reclassifications out of Accumulated Comprehensive Income (Loss) [Line Items]
Interest Expense								(4.3)
Pension & Postretirement
Schedule of Reclassifications out of Accumulated Comprehensive Income (Loss) [Line Items]
Net of Tax		$ (0.5)	$ (0.6)		$ (1.2)	$ (1.2)	2.3	(1.1)
Pension & Postretirement | Reclassification out of Accumulated Other Comprehensive Income
Schedule of Reclassifications out of Accumulated Comprehensive Income (Loss) [Line Items]
Total before tax	(1.0)			(1.1)			(2.9)	(3.5)
Tax expense	3.3						4.1
Net of Tax	2.3			(1.1)			1.2	(3.5)
Actuarial losses | Reclassification out of Accumulated Other Comprehensive Income
Schedule of Reclassifications out of Accumulated Comprehensive Income (Loss) [Line Items]
Total before tax	(1.3)			$ (1.1)			(3.9)	$ (3.5)
Prior service cost | Reclassification out of Accumulated Other Comprehensive Income
Schedule of Reclassifications out of Accumulated Comprehensive Income (Loss) [Line Items]
Total before tax	$ 0.3						$ 1.0