Derivatives (Derivatives in Cash Flow Hedging Relationships) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Not Designated as Hedging Instrument [Member]
Effect of Derivative Instruments on Consolidated Statements of Operations
Amount of Loss (Gain) Recognized in Income on Derivatives	$ 3.4	$ 2.8	$ 0.4
Not Designated as Hedging Instrument [Member] \| Losses and Other Expenses, Net [Member] \| Commodity Futures Contracts [Member]
Effect of Derivative Instruments on Consolidated Statements of Operations
Amount of Loss (Gain) Recognized in Income on Derivatives	(0.9)	2.5	1.2
Not Designated as Hedging Instrument [Member] \| Losses and Other Expenses, Net [Member] \| Foreign Currency Forward Contracts [Member]
Effect of Derivative Instruments on Consolidated Statements of Operations
Amount of Loss (Gain) Recognized in Income on Derivatives	4.3	0.3	(0.8)
Cash Flow Hedging [Member] \| Cost of Goods Sold [Member] \| Commodity Futures Contracts [Member]
Effect of Derivative Instruments on Consolidated Statements of Operations
Amount of Loss (Gain) Reclassified from AOCI into Income (Effective Portion)	12.3	12.5	5.8
Cash Flow Hedging [Member] \| Losses and Other Expenses, Net [Member] \| Commodity Futures Contracts [Member]
Effect of Derivative Instruments on Consolidated Statements of Operations
Amount of Loss (Gain) Recognized in Income on Derivatives (Ineffective Portion)	$ (1.6)	$ 0.1	$ 0.1

Effect of derivative instruments on consolidated statements of operation.

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- Definition

Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5618551-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (a),(c),(d),(e)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4D
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624177-113959

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4C
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=64837297&loc=SL5624171-113959

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 25
-Section 50
-Paragraph 1
-Subparagraph (a)(1),(2)
-URI http://asc.fasb.org/extlink&oid=6886632&loc=d3e76258-113986

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