Debt - Schedule of Carrying Value of Individual Components of Debt (Details) - USD ($) $ in Millions	Jun. 30, 2019	Sep. 30, 2018
Debt Instrument [Line Items]
Total debt	$ 10,538.2	$ 6,415.2
Less: current portion of debt	779.1	740.7
Long-term debt due after one year	9,759.1	5,674.5
Notes Due Fiscal 2019 to 2022 [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Total debt	509.1	1,470.9
Notes Due Fiscal 2023 to 2028 [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Total debt	3,768.0	2,534.4
Notes Due Fiscal 2029 to 2033 [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Total debt	2,200.6	964.1
Notes Due Fiscal 2037 to 2047 [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Total debt	179.0	178.5
Term Loan Facilities [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Total debt	2,506.9	599.4
Revolving Credit and Swing Facilities [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Total debt	405.3	355.0
Receivables Facility [Member] \| Secured Debt [Member]
Debt Instrument [Line Items]
Total debt	150.0
Commercial Paper [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Total debt	445.6
Capital Lease Obligations [Member] \| Secured Debt [Member]
Debt Instrument [Line Items]
Total debt	188.5	171.0
Supplier Financing and Commercial Card Programs [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Total debt	126.8	105.1
International and Other Debt [Member]
Debt Instrument [Line Items]
Total debt	$ 58.4	$ 36.8

Amount of short-term debt and current maturity of long-term debt and capital lease obligations due within one year or the normal operating cycle, if longer.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.19,20)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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- Definition

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+ References

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- Definition

Represents the aggregate of total long-term debt, including current maturities and short-term debt.

+ References

No definition available.

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- Definition

Amount after unamortized (discount) premium and debt issuance costs of long-term debt classified as noncurrent and excluding amounts to be repaid within one year or the normal operating cycle, if longer. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22)
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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