Ratio of consolidated EBITDA for four preceding quarters to consolidated interest expense for four preceding quarters.

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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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No definition available.

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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average interest rate of debt outstanding.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Amount of cash paid for interest, excluding capitalized interest, classified as operating activity. Includes, but is not limited to, payment to settle zero-coupon bond for accreted interest of debt discount and debt instrument with insignificant coupon interest rate in relation to effective interest rate of borrowing attributable to accreted interest of debt discount.

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Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

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Fair value of the amount outstanding under the credit facility.

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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Period between issuance and maturity of long-term debt, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Long-term and Short-term Debt - Narrative (Details)				1 Months Ended			12 Months Ended
Long-term and Short-term Debt - Narrative (Details)	Aug. 31, 2021 USD ($)	Mar. 01, 2019 USD ($)	Nov. 13, 2018 USD ($)	Sep. 30, 2020 USD ($)	Mar. 31, 2019 USD ($)	Nov. 12, 2018 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Apr. 30, 2020 USD ($)
Debt Instrument [Line Items]
Short-term debt				$ 24,600,000			$ 509,700,000	$ 24,600,000
Interest payments							$ 91,800,000	101,700,000	$ 97,500,000
0.35% notes, payable in August 2023
Debt Instrument [Line Items]
Stated interest rate							0.00003%
2.80% notes, payable in August 2061
Debt Instrument [Line Items]
Stated interest rate							0.028%
Notes Payable, Other Payables
Debt Instrument [Line Items]
Debt instrument, face amount	$ 1,500,000,000				$ 1,000,000,000
Notes Payable, Other Payables \| 0.35% notes, payable in August 2023
Debt Instrument [Line Items]
Debt instrument, face amount	$ 600,000,000
Stated interest rate	0.35%
Notes Payable, Other Payables \| 1.750% Notes Due August 2031 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount	$ 450,000,000
Stated interest rate	1.75%
Notes Payable, Other Payables \| 2.80% notes, payable in August 2061
Debt Instrument [Line Items]
Debt instrument, face amount	$ 450,000,000
Stated interest rate	2.80%
Notes Payable, Other Payables \| 4.200% Notes Due March 2049 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount					$ 575,000,000
Stated interest rate					4.20%
Proceeds from issuance of debt	$ 1,485,600,000				$ 987,600,000
Notes Payable, Other Payables \| 3.500% Notes Due March 2029 [Member]
Debt Instrument [Line Items]
Debt instrument, face amount					$ 425,000,000
Stated interest rate					3.50%
Line of Credit \| Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, term			5 years			5 years
Line of credit facility, current borrowing capacity			$ 1,250,000,000			$ 1,000,000,000
Borrowing capacity			$ 750,000,000
Line of credit facility, fair value of amount outstanding				0			$ 0	0
Maximum ratio of EBITDA to interest expense under credit facility							3.0
Treasury locks
Debt Instrument [Line Items]
Derivative, gain (loss) on derivative, net	$ 28,000,000	$ 35,700,000
Commercial Paper
Debt Instrument [Line Items]
Short-term debt				0			$ 484,000,000	0
Debt, weighted average interest rate							18.00%
Interest Bearing Loan
Debt Instrument [Line Items]
Short-term debt				23,500,000			$ 23,500,000	$ 23,500,000
Notes Payable to Banks
Debt Instrument [Line Items]
Debt instrument, face amount										$ 400,000,000
Long-term debt, term										364 days
Repayments of debt				$ 400,000,000