Debt - Schedule of Carrying Value of Individual Components of Debt (Details) - USD ($) $ in Millions	Mar. 31, 2020	Sep. 30, 2019
Debt Instrument [Line Items]
Total debt	$ 10,856.6	$ 10,063.4
Less: current portion of debt	432.0	561.1
Long-term debt due after one year	10,424.6	9,502.3
Notes Due Fiscal 2020 to 2022 [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Total debt	505.3	507.8
Notes Due Fiscal 2023 to 2028 [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Total debt	3,771.3	3,769.1
Notes Due Fiscal 2029 to 2033 [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Total debt	2,191.5	2,197.6
Notes Due Fiscal 2037 to 2047 [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Total debt	178.8	179.0
Term Loan Facilities [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Total debt	2,096.3	2,295.5
Revolving Credit and Swing Facilities [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Total debt	807.1	396.0
Receivables Securitization [Member] \| Secured Debt [Member]
Debt Instrument [Line Items]
Total debt	475.0
Commercial Paper [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Total debt	304.5	339.2
Finance Lease Obligations [Member] \| Secured Debt [Member]
Debt Instrument [Line Items]
Total debt	280.7	185.8
Supplier Financing and Commercial Card Programs [Member] \| Unsecured Debt [Member]
Debt Instrument [Line Items]
Total debt	108.4	123.2
International and Other Debt [Member]
Debt Instrument [Line Items]
Total debt	$ 137.7	$ 70.2

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

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

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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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