Derivative Financial Instruments and Hedging (Details) - USD ($) $ in Millions	Sep. 30, 2018	Sep. 30, 2017
Derivatives, Fair Value
Derivative Liability	$ 141.4	$ 243.5
Derivative Asset	66.4	5.9
Level 2
Derivatives, Fair Value
Asset Derivatives:		5.9
Liability Derivatives:		243.5
Derivative Liability	141.4	243.5
Derivative Asset	66.4	5.9
Portion Designated as Hedging Instruments \| Level 2
Derivatives, Fair Value
Asset Derivatives:	55.7	1.4
Liability Derivatives:	20.8	30.0
Commodity contracts \| Level 2 \| Prepaid expenses and other current assets
Derivatives, Fair Value
Asset Derivatives:	1.9	0.5
Commodity contracts \| Level 2 \| Other Assets
Derivatives, Fair Value
Asset Derivatives:	0.2	0.0
Commodity contracts \| Level 2 \| Other current liabilities
Derivatives, Fair Value
Liability Derivatives:	2.2	1.9
Commodity contracts \| Not Designated as Hedging Instrument
Derivatives, Fair Value
Derivative, Notional Amount	64.3	53.8
Commodity contracts \| Portion Designated as Hedging Instruments \| Level 2 \| Prepaid expenses and other current assets
Derivatives, Fair Value
Asset Derivatives:	0.0	0.0
Commodity contracts \| Portion Designated as Hedging Instruments \| Level 2 \| Other Assets
Derivatives, Fair Value
Asset Derivatives:	0.0	0.0
Commodity contracts \| Portion Designated as Hedging Instruments \| Level 2 \| Other current liabilities
Derivatives, Fair Value
Liability Derivatives:	0.0	0.0
Energy contracts \| Level 2 \| Prepaid expenses and other current assets
Derivatives, Fair Value
Asset Derivatives:	4.9	3.8
Energy contracts \| Level 2 \| Other Assets
Derivatives, Fair Value
Asset Derivatives:	0.3	0.0
Energy contracts \| Level 2 \| Other current liabilities
Derivatives, Fair Value
Liability Derivatives:	0.4	0.3
Energy contracts \| Not Designated as Hedging Instrument
Derivatives, Fair Value
Derivative, Notional Amount	20.8	25.6
Energy contracts \| Portion Designated as Hedging Instruments \| Level 2 \| Prepaid expenses and other current assets
Derivatives, Fair Value
Asset Derivatives:	0.0	0.0
Energy contracts \| Portion Designated as Hedging Instruments \| Level 2 \| Other Assets
Derivatives, Fair Value
Asset Derivatives:	0.0	0.0
Energy contracts \| Portion Designated as Hedging Instruments \| Level 2 \| Other current liabilities
Derivatives, Fair Value
Liability Derivatives:	0.0	0.0
Foreign exchange contracts \| Level 2 \| Prepaid expenses and other current assets
Derivatives, Fair Value
Asset Derivatives:	1.2	1.3
Foreign exchange contracts \| Level 2 \| Other Assets
Derivatives, Fair Value
Asset Derivatives:	17.6	0.3
Foreign exchange contracts \| Level 2 \| Other current liabilities
Derivatives, Fair Value
Liability Derivatives:	1.5	1.5
Foreign exchange contracts \| Level 2 \| Other liabilities
Derivatives, Fair Value
Liability Derivatives:	19.4	23.6
Foreign exchange contracts \| Not Designated as Hedging Instrument
Derivatives, Fair Value
Derivative, Notional Amount	9.3	3.8
Foreign exchange contracts \| Portion Designated as Hedging Instruments
Derivatives, Fair Value
Derivative, Notional Amount	0.0	20.9
Foreign exchange contracts \| Portion Designated as Hedging Instruments \| Level 2 \| Prepaid expenses and other current assets
Derivatives, Fair Value
Asset Derivatives:	1.1	1.1
Foreign exchange contracts \| Portion Designated as Hedging Instruments \| Level 2 \| Other Assets
Derivatives, Fair Value
Asset Derivatives:	17.6	0.3
Foreign exchange contracts \| Portion Designated as Hedging Instruments \| Level 2 \| Other current liabilities
Derivatives, Fair Value
Liability Derivatives:	1.4	1.5
Foreign exchange contracts \| Portion Designated as Hedging Instruments \| Level 2 \| Other liabilities
Derivatives, Fair Value
Liability Derivatives:	19.4	23.6
Currency Swap \| Portion Designated as Hedging Instruments
Derivatives, Fair Value
Derivative, Notional Amount	662.9	448.7
Interest rate swaps \| Level 2 \| Prepaid expenses and other current assets
Derivatives, Fair Value
Liability Derivatives:	6.4	0.0
Interest rate swaps \| Level 2 \| Other Assets
Derivatives, Fair Value
Liability Derivatives:	33.9	0.0
Interest rate swaps \| Level 2 \| Other current liabilities
Derivatives, Fair Value
Liability Derivatives:	23.6	50.9
Interest rate swaps \| Level 2 \| Other liabilities
Derivatives, Fair Value
Liability Derivatives:	94.3	165.3
Interest rate swaps \| Not Designated as Hedging Instrument
Derivatives, Fair Value
Derivative, Notional Amount	74.6	76.1
Interest rate swaps \| Portion Designated as Hedging Instruments
Derivatives, Fair Value
Derivative, Notional Amount	1,000.0	1,000.0
Interest rate swaps \| Portion Designated as Hedging Instruments \| Level 2 \| Prepaid expenses and other current assets
Derivatives, Fair Value
Liability Derivatives:	6.4	0.0
Interest rate swaps \| Portion Designated as Hedging Instruments \| Level 2 \| Other Assets
Derivatives, Fair Value
Liability Derivatives:	30.6	0.0
Interest rate swaps \| Portion Designated as Hedging Instruments \| Level 2 \| Other current liabilities
Derivatives, Fair Value
Liability Derivatives:	0.0	0.7
Interest rate swaps \| Portion Designated as Hedging Instruments \| Level 2 \| Other liabilities
Derivatives, Fair Value
Liability Derivatives:	0.0	4.2
Interest rate swap, rate lock swaps \| Not Designated as Hedging Instrument
Derivatives, Fair Value
Derivative, Notional Amount	$ 1,649.3	$ 1,649.3

Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
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