Financial Instruments - Income Statement (Details) - USD ($) $ in Millions	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Derivatives, Fair Value [Line Items]
Sales Revenue, Goods, Net	$ 2,784.3	$ 2,407.0
Cost of sales	2,192.5	1,890.7
Selling, general and administrative expenses	253.4	219.0
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income, Effective Portion, Net [Abstract]
Gain (loss) expected to be reclassified in one year or less	(4.8)
Commodity contracts
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income, Effective Portion, Net [Abstract]
Gain (loss) expected to be reclassified in one year or less	(0.1)
Foreign currency
Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income, Effective Portion, Net [Abstract]
Gain (loss) expected to be reclassified in one year or less	(4.7)
Cross Currency Interest Rate Contract [Member] \| Interest expense and finance charges
Derivatives Designated As Net Investment Hedges Under Topic 815 Abstract
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net	1.3	0.0
Foreign currency denominated debt designated as a net investment hedge [Member] \| SG&A expense
Derivatives Designated As Net Investment Hedges Under Topic 815 Abstract
Derivative Instruments, Gain (Loss) Recognized in Income, Ineffective Portion and Amount Excluded from Effectiveness Testing, Net	(3.7)	(0.9)
Cash Flow Hedging [Member] \| Commodity contracts \| Sales Revenue, Net [Member]
Derivatives Designated As Net Investment Hedges Under Topic 815 Abstract
Gain (loss) reclassified from accumulated OCI into net income, effective portion, net	0.0	0.0
Gain (Loss) on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring, Net	0.0	0.0
Cash Flow Hedging [Member] \| Commodity contracts \| Cost of goods sold
Derivatives Designated As Net Investment Hedges Under Topic 815 Abstract
Gain (loss) reclassified from accumulated OCI into net income, effective portion, net	0.0	0.2
Gain (Loss) on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring, Net	0.0	0.0
Cash Flow Hedging [Member] \| Commodity contracts \| SG&A expense
Derivatives Designated As Net Investment Hedges Under Topic 815 Abstract
Gain (loss) reclassified from accumulated OCI into net income, effective portion, net	0.0	0.0
Gain (Loss) on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring, Net	0.0	0.0
Cash Flow Hedging [Member] \| Foreign currency \| Sales Revenue, Net [Member]
Derivatives Designated As Net Investment Hedges Under Topic 815 Abstract
Gain (loss) reclassified from accumulated OCI into net income, effective portion, net	(0.1)	1.1
Gain (Loss) on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring, Net	0.0	0.0
Cash Flow Hedging [Member] \| Foreign currency \| Cost of goods sold
Derivatives Designated As Net Investment Hedges Under Topic 815 Abstract
Gain (loss) reclassified from accumulated OCI into net income, effective portion, net	(1.1)	0.8
Gain (Loss) on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring, Net	0.0	0.0
Cash Flow Hedging [Member] \| Foreign currency \| SG&A expense
Derivatives Designated As Net Investment Hedges Under Topic 815 Abstract
Gain (loss) reclassified from accumulated OCI into net income, effective portion, net	0.0	0.0
Gain (Loss) on Discontinuation of Cash Flow Hedge Due to Forecasted Transaction Probable of Not Occurring, Net	$ 0.0	$ 0.1

Derivatives Designated As Net Investment Hedges Under Topic 815 Abstract.

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The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
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Total costs related to goods produced and sold during the reporting period.

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The effective portion of net gain (loss) reclassified from accumulated other comprehensive income into income on derivative instruments designated and qualifying as hedging instruments.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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The portion of gains and losses (net) on derivative instruments designated and qualifying as hedging instruments representing (a) the amount of the hedge ineffectiveness and (b) the amount, if any, excluded from the assessment of hedge effectiveness.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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The amount of net gain (loss) reclassified into earnings in the period when cash flow hedge is discontinued because it is probable that the original forecasted transactions will not occur by the end of the original period or an additional two month time period.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Aggregate revenue during the period from the sale of goods in the normal course of business, after deducting returns, allowances and discounts.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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