Derivative Instruments and Hedging Activities - Effects of Derivative Instruments on the Condensed Consolidated Statements of Income and Changes in AOCI (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Derivatives Not Designated as Hedging Instruments
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Income	$ (154.0)	$ 18.4
Cash Flow Hedges
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in AOCI	(1.9)	(0.6)
Gain (Loss) Reclassified from AOCI into Income	(1.0)	0.5
Foreign currency contracts \| Derivatives Not Designated as Hedging Instruments \| Other non-operating income (expense), net
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Income	8.9	(4.8)
Foreign currency contracts \| Cash Flow Hedges
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in AOCI	1.0	(1.4)
Foreign currency contracts \| Cash Flow Hedges \| Cost of sales
Derivative Instruments, Gain (Loss)
Gain (Loss) Reclassified from AOCI into Income	0.8	0.8
Foreign currency contracts \| Net Investment Hedges
Derivative Instruments, Gain (Loss)
Gain (loss) recognized in AOCI, net investment hedge	0.9	0.0
Cross-currency contracts \| Cash Flow Hedges
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in AOCI	(0.1)	0.1
Cross-currency contracts \| Cash Flow Hedges \| Interest expense/other operating income, net
Derivative Instruments, Gain (Loss)
Gain (Loss) Reclassified from AOCI into Income	(0.3)	0.2
Interest rate contracts \| Cash Flow Hedges
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in AOCI	(2.8)	0.7
Interest rate contracts \| Cash Flow Hedges \| Interest expense
Derivative Instruments, Gain (Loss)
Gain (Loss) Reclassified from AOCI into Income	(1.5)	(0.5)
Commodity contracts \| Derivatives Not Designated as Hedging Instruments \| Cost of sales
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Income	(159.7)	24.4
Commodity contracts \| Derivatives Not Designated as Hedging Instruments \| Revenues
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Income	(2.8)	(1.3)
Commodity contracts \| Derivatives Not Designated as Hedging Instruments \| Operating and administrative expenses
Derivative Instruments, Gain (Loss)
Gain (Loss) Recognized in Income	$ (0.4)	$ 0.1

Derivative Instruments, Gain (Loss) Recognized in Other Comprehensive Income (Loss)

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+ References

No definition available.

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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=84234895&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=84234895&loc=SL5624177-113959

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

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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