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

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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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The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

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Debt (Narrative) (Details) - USD ($) $ in Millions		1 Months Ended	6 Months Ended
Debt (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2021	Nov. 30, 2021	Mar. 31, 2022	Mar. 31, 2021	Sep. 30, 2021
Debt Instrument [Line Items]
Repayment of debt			$ 400.0	$ 15.9
Note 3.0% \| Senior Notes
Debt Instrument [Line Items]
Interest rate (percent)		3.00%
Repayment of debt		$ 400.0
2021 Credit Agreement \| Revolving credit agreement
Debt Instrument [Line Items]
Term of credit facility (in years)	5 years
Maximum borrowing capacity	$ 2,500.0		2,750.0	$ 2,500.0
Borrowings outstanding			0.0
Credit facilities of foreign subsidiaries \| Foreign credit facilities
Debt Instrument [Line Items]
Maximum borrowing capacity			486.5
Borrowings outstanding			$ 446.9		$ 176.2