Derivative Financial Instruments (Derivative Gains and Losses Included in AOCI and Expected to be Reclassified into Earnings in 12 Months, Net of Tax) (Details) - USD ($) $ in Millions	3 Months Ended
Jun. 30, 2019	Sep. 30, 2018
Cash Flow Hedging [Member] \| Interest Rate Contract [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Net Gains/(Losses) Included in AOCI	$ 3.0	$ 24.7
Net Gains/(Losses) Expected to be Reclassified from AOCI into Earnings within 12 Months	$ 2.4
Outstanding Contract Remaining Maturity (Months)	0 months
Cash Flow Hedging [Member] \| Cross-Currency Swap [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Net Gains/(Losses) Included in AOCI	$ (3.1)	(12.6)
Net Gains/(Losses) Expected to be Reclassified from AOCI into Earnings within 12 Months	$ 0.0
Outstanding Contract Remaining Maturity (Months)	65 months
Cash Flow Hedging [Member] \| Foreign Currency Contract - Other [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Net Gains/(Losses) Included in AOCI	$ 6.2	5.8
Net Gains/(Losses) Expected to be Reclassified from AOCI into Earnings within 12 Months	$ 3.6
Outstanding Contract Remaining Maturity (Months)	36 months
Cash Flow Hedging [Member] \| Coffee Contracts [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Net Gains/(Losses) Included in AOCI	$ 0.0	(0.2)
Net Gains/(Losses) Expected to be Reclassified from AOCI into Earnings within 12 Months	$ 0.0
Outstanding Contract Remaining Maturity (Months)	30 months
Net Investment Hedging [Member] \| Foreign Currency Contract - Other [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Net Gains/(Losses) Included in AOCI	$ 16.0	16.0
Net Gains/(Losses) Expected to be Reclassified from AOCI into Earnings within 12 Months	$ 0.0
Outstanding Contract Remaining Maturity (Months)	0 months
Net Investment Hedging [Member] \| ForeignExchangeYenDebt [Member]
Derivative Instruments and Hedging Activities Disclosures [Line Items]
Net Gains/(Losses) Included in AOCI	$ (26.3)	$ 3.6
Net Gains/(Losses) Expected to be Reclassified from AOCI into Earnings within 12 Months	$ 0.0
Outstanding Contract Remaining Maturity (Months)	57 months

Accumulated change, net of tax, in accumulated gains and losses from derivative instruments designated and qualifying as the effective portion of cash flow hedges. Includes an entity's share of an equity investee's Increase or Decrease in deferred hedging gains or losses.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 11
-URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e637-108580

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 10A
-Subparagraph (d)
-URI http://asc.fasb.org/extlink&oid=118930883&loc=SL7669646-108580

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
-Paragraph 14
-URI http://asc.fasb.org/extlink&oid=118930883&loc=d3e681-108580

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- Definition

The estimated net amount of existing gains or losses on cash flow hedges at the reporting date expected to be reclassified to earnings within the next 12 months.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 30
-Section 50
-Paragraph 1
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Period remaining until the derivative contract matures, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 830
-SubTopic 30
-Section 45
-Paragraph 20
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