Derivative Instruments and Hedging Activities (Details 2) - USD ($) $ in Millions	Jun. 30, 2018	Dec. 31, 2017
Designated as Hedging Instrument [Member] \| Commodity Contract [Member] \| Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Current	$ 4.2	$ 9.0
Designated as Hedging Instrument [Member] \| Commodity Contract [Member] \| Other Non-current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Noncurrent	0.2	2.3
Designated as Hedging Instrument [Member] \| Commodity Contract [Member] \| Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Current	(3.2)	(4.6)
Designated as Hedging Instrument [Member] \| Commodity Contract [Member] \| Other Non-current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Noncurrent	(1.6)	(0.5)
Designated as Hedging Instrument [Member] \| Foreign Exchange Contract [Member] \| Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Current	0.1	0.2
Designated as Hedging Instrument [Member] \| Foreign Exchange Contract [Member] \| Other Non-current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Noncurrent	1.0	1.7
Designated as Hedging Instrument [Member] \| Foreign Exchange Contract [Member] \| Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Current	(0.8)	(0.2)
Designated as Hedging Instrument [Member] \| Foreign Exchange Contract [Member] \| Other Non-current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Noncurrent	(0.9)	0.0
Not Designated as Hedging Instrument [Member] \| Commodity Contract [Member] \| Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Current	11.9	26.2
Not Designated as Hedging Instrument [Member] \| Commodity Contract [Member] \| Other Non-current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Noncurrent	2.1	8.3
Not Designated as Hedging Instrument [Member] \| Commodity Contract [Member] \| Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Current	(0.3)	(0.3)
Not Designated as Hedging Instrument [Member] \| Commodity Contract [Member] \| Other Non-current Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Noncurrent	(0.2)	0.0
Not Designated as Hedging Instrument [Member] \| Foreign Exchange Contract [Member] \| Other Current Assets [Member]
Derivatives, Fair Value [Line Items]
Derivative Asset, Current	0.3	0.0
Not Designated as Hedging Instrument [Member] \| Foreign Exchange Contract [Member] \| Accrued Liabilities [Member]
Derivatives, Fair Value [Line Items]
Derivative Liability, Current	$ 0.0	$ (0.1)

Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, expected to be settled within one year or normal operating cycle, if longer. Includes assets not subject to a master netting arrangement and not elected to be offset.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
-Paragraph 3
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312

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