Amount of debt repurchase plan authorized.

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Maximum borrowing capacity of letter of credit.

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Letter of Credit, Maximum Borrowing Capacity, Percentage of Revolving Credit Commitment

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

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Effective interest rate for the funds borrowed under the debt agreement considering interest compounding and original issue discount or premium.

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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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Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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No definition available.

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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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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.

+ References

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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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Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

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Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

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The cash inflow from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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The cash outflow for the settlement of obligation drawn from a contractual arrangement with the lender, including letter of credit, standby letter of credit and revolving credit arrangements, under which borrowings can be made up to a specific amount at any point in time with maturities due beyond one year or the operating cycle, if longer.

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Debt, net - Additional Information (Details) - USD ($) $ in Millions	6 Months Ended
	Mar. 31, 2022	Sep. 30, 2021	Apr. 30, 2020
Debt Instrument [Line Items]
Line of Credit Facility, Current Borrowing Capacity	$ 410.0
Line of Credit Facility, Maximum Borrowing Capacity	600.0
Letter of Credit, Maximum Borrowing Capacity	$ 100.0
Letter of Credit, Maximum Borrowing Capacity, Percentage of Revolving Credit Commitment	50.00%
Repayments of Long-term Lines of Credit	$ 0.0
Proceeds from Long-term Lines of Credit	0.0
Long-term Line of Credit	0.0	$ 0.0
Letters of credit outstanding	60.5
Line of Credit Facility, Remaining Borrowing Capacity	349.5
Debt	705.3	704.5
Debt Repurchase Program, Authorized Amount	30.0		$ 30.0
Senior Notes [Member]
Debt Instrument [Line Items]
Deferred finance costs, net	7.2	8.0
Senior Notes 3.85%
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 400.0
Interest rate percentage	3.85%
Debt Instrument, Redemption Price, Percentage	101.925%
Effective interest rate of liability component	4.10%
Debt	$ 396.0	395.5
Senior Notes 5.0%
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 300.0
Interest rate percentage	5.00%
Debt Instrument, Redemption Price, Percentage	102.50%
Effective interest rate of liability component	5.20%
Debt	$ 296.8	296.5
Secured Debt
Debt Instrument [Line Items]
Interest rate percentage	4.00%
Debt	$ 12.5	$ 12.5