Derivatives (Details 2) - USD ($) $ in Millions	Jun. 30, 2015	Dec. 31, 2014
Information about derivative instruments measured at fair value and their locations on the consolidated balance sheet
Derivative asset	$ 496.9	$ 695.3
Derivative liability	473.4	649.6
Derivative, credit-risk related contingent features
Net liability position	35.9	111.7
Collateral posted	28.9	89.4
Additional assets required to be posted should credit-risk contingent feature be triggered	7.0	22.3
Derivatives designated as hedging instruments
Information about derivative instruments measured at fair value and their locations on the consolidated balance sheet
Derivative asset	5.8	23.5
Derivative liability	2.4	1.7
Derivatives designated as hedging instruments \| Commodity contracts \| Short-term derivative assets, net
Information about derivative instruments measured at fair value and their locations on the consolidated balance sheet
Derivative asset	5.0	18.8
Derivative liability	1.8	1.0
Derivatives designated as hedging instruments \| Commodity contracts \| Accrued expenses and other current liabilities
Information about derivative instruments measured at fair value and their locations on the consolidated balance sheet
Derivative asset	0.8	4.7
Derivative liability	0.6	0.7
Derivatives not designated as hedging instruments
Information about derivative instruments measured at fair value and their locations on the consolidated balance sheet
Derivative asset	491.1	671.8
Derivative liability	471.0	647.9
Derivatives not designated as hedging instruments \| Commodity contracts \| Short-term derivative assets, net
Information about derivative instruments measured at fair value and their locations on the consolidated balance sheet
Derivative asset	272.6	399.0
Derivative liability	128.9	76.0
Derivatives not designated as hedging instruments \| Commodity contracts \| Identifiable intangible and other non-current assets
Information about derivative instruments measured at fair value and their locations on the consolidated balance sheet
Derivative asset	8.9	12.1
Derivative liability	1.9	0.6
Derivatives not designated as hedging instruments \| Commodity contracts \| Accrued expenses and other current liabilities
Information about derivative instruments measured at fair value and their locations on the consolidated balance sheet
Derivative asset	200.3	234.1
Derivative liability	326.4	530.0
Derivatives not designated as hedging instruments \| Commodity contracts \| Other long-term liabilities
Information about derivative instruments measured at fair value and their locations on the consolidated balance sheet
Derivative asset	3.3	4.8
Derivative liability	5.2	29.3
Derivatives not designated as hedging instruments \| Foreign currency contracts \| Short-term derivative assets, net
Information about derivative instruments measured at fair value and their locations on the consolidated balance sheet
Derivative asset	1.6	21.3
Derivative liability	1.3	12.0
Derivatives not designated as hedging instruments \| Foreign currency contracts \| Identifiable intangible and other non-current assets
Information about derivative instruments measured at fair value and their locations on the consolidated balance sheet
Derivative asset	0.1	$ 0.5
Derivatives not designated as hedging instruments \| Foreign currency contracts \| Accrued expenses and other current liabilities
Information about derivative instruments measured at fair value and their locations on the consolidated balance sheet
Derivative asset	4.2
Derivative liability	6.9
Derivatives not designated as hedging instruments \| Foreign currency contracts \| Other long-term liabilities
Information about derivative instruments measured at fair value and their locations on the consolidated balance sheet
Derivative asset	0.1
Derivative liability	$ 0.4

The aggregate fair value of additional assets that would be required to be posted as collateral for derivative instruments with credit-risk-related contingent features if the credit-risk-related contingent features were triggered at the end of the reporting period.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (e)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624258-113959

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The aggregate fair value of assets that are already posted, at the end of the reporting period, as collateral for derivative instruments with credit-risk-related contingent features.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624258-113959

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Fair value, before 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. Includes assets not subject to a master netting arrangement and elected not to be offset.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 20

-Section 50

-Paragraph 3

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=34720828&loc=SL20225862-175312

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- References

No definition available.

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Fair value, before effects of master netting arrangements, of a financial liability or 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. Includes liabilities not subject to a master netting arrangement and elected not to be offset.

+ References

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- Definition

The aggregate fair value amounts of derivative instruments that contain credit-risk-related contingent features that are in a net liability position at the end of the reporting period. For nonderivative instruments that are designated and qualify as hedging instruments, the fair value amounts are the carrying value of the nonderivative hedging instrument, including the adjustment for the foreign currency transaction gain (loss) on that instrument.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4H

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5624258-113959

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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.

+ References

No definition available.

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