Percentage points added to the reference rate to compute the variable rate on the debt instrument.

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Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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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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Weighted average interest rate of debt outstanding.

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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 carrying amount of the asset transferred to a third party to serve as a deposit, which typically serves as security against failure by the transferor to perform under terms of an agreement.

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Fixed interest rate related to the interest rate derivative.

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Nominal or face amount used to calculate payment on derivative.

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Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

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Reflects the difference between the fair value of payments made to legally extinguish a debt and its carrying value at that time. This item excludes the write-off of amounts previously capitalized as debt issuance costs.

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Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

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Amount of cash paid for interest, including, but not limited to, capitalized interest and payment to settle zero-coupon bond attributable to 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; classified as operating and investing activities.

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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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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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Fair value portion of contractual arrangement with a lender under which borrowings can be made up to a specific amount at any point in time.

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The cash outflow paid to third parties in connection with debt origination, which will be amortized over the remaining maturity period of the associated long-term debt.

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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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Carrying amount of accrued known and estimated losses incurred as of the balance sheet date for which no insurance coverage exists, and for which a claim has been made or is probable of being asserted, typically arising from workmen's compensation-type of incidents and personal injury to nonemployees from accidents on the entity's property that are expected to be paid within one year (or the normal operating cycle, if longer).

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Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Financing Arrangements - Credit Facility (Details) $ in Thousands, £ in Millions		12 Months Ended
	Mar. 27, 2020 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2020 GBP (£)
Financial arrangement
Letters of credit outstanding		$ 100,000
Loss on extinguishment of debt		(16,090)
Self-insurance liabilities		5,100	$ 7,400
Letters of credit primarily for self-insured liabilities
Financial arrangement
Letters of Credit and bank guarantees outstanding		4,000
Fair value of instruments		0
Performance guarantee
Financial arrangement
Letters of credit outstanding		96,000
United Kingdom
Financial arrangement
Borrowings outstanding under credit agreement		6,700
Maximum borrowing capacity under credit agreement		25,800			£ 20.0
Cash on deposit as collateral		25,500
Interest Rate Swaps \| Instruments designated as accounting hedges:
Financial arrangement
Notional principal outstanding derivative instruments		595,000	95,000
Revolving Credit Agreement
Financial arrangement
Borrowings outstanding under credit agreement			226,500
Maximum borrowing capacity under credit agreement			800,000
Other credit facility
Financial arrangement
Letters of credit outstanding		6,900
Senior unsecured notes
Financial arrangement
Long-term debt, gross			$ 200,000
Principal payments on long-term borrowings	$ 189,300
Loss on extinguishment of debt	(16,100)
Loss on extinguishment of debt, payment to note holders	(15,900)
Loss on extinguishment of debt, write-off of debt issuance costs	200
Senior unsecured notes \| Minimum
Financial arrangement
Interest rate (as a percent)			3.35%
Senior unsecured notes \| Maximum
Financial arrangement
Interest rate (as a percent)			3.93%
Term Loan from a group of financial institutions
Financial arrangement
Long-term debt, gross		$ 444,375
Credit Facility
Financial arrangement
Weighted average interest rate on outstanding borrowings (as a percent)		2.15%			2.15%
Amount of interest paid		$ 20,100	$ 16,800	$ 10,000
Debt issuance costs incurred	$ 3,400
Unamortized debt issuance costs		$ 5,600
Credit Facility \| Interest Rate Swaps \| Instruments designated as accounting hedges:
Financial arrangement
Fixed interest rate of derivative instrument (as a percent)		2.74%			2.74%
Notional principal outstanding derivative instruments		$ 500,000
Credit Facility \| LIBOR \| Minimum
Financial arrangement
Variable interest rate (as a percent)	1.00%
Credit Facility \| LIBOR \| Maximum
Financial arrangement
Variable interest rate (as a percent)	2.00%
Credit Facility \| Revolving Credit Agreement
Financial arrangement
Borrowings outstanding under credit agreement		209,000
Letters of credit outstanding		93,100
Maximum borrowing capacity under credit agreement	$ 850,000		$ 800,000
Available amount under line of credit		547,900
Credit Facility \| Term Loan from a group of financial institutions
Financial arrangement
Principal amount of debt instrument	$ 450,000
Long-term debt, gross		$ 444,400