Debt (Schedule Of Debt) (Details) - USD ($)	3 Months Ended
Nov. 28, 2020	Aug. 29, 2020
Debt Instrument [Line Items]
Financing arrangements	$ 1,267,000	$ 194,000
Obligations under finance leases	3,395,000	3,715,000
Less: unamortized debt issuance costs	(732,000)	(843,000)
Total debt, including obligations under finance leases	490,130,000	619,266,000
Less: current portion, including obligations under finance leases	(23,225,000)	(122,248,000)
Total long-term debt, including obligations under finance leases	466,905,000	497,018,000
Financing obligations, current	1,162,000	194,000
Current finance lease liabilities	1,271,000	1,262,000
Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility	120,000,000	250,000,000
Short-term debt		100,000,000
Committed Bank Facility [Member]
Debt Instrument [Line Items]
Credit facility	$ 100,000,000
Maturity date	Apr. 14, 2022
Uncommitted Bank Facilities [Member]
Debt Instrument [Line Items]
Credit facility	$ 1,200,000	1,200,000
Short-term debt	1,200,000	1,200,000
Senior Notes Series A [Member] \| Private Placement Debt [Member]
Debt Instrument [Line Items]
Principal amount	$ 75,000,000	75,000,000
Interest rate	2.65%
Maturity date	Jul. 28, 2023
Senior Notes Series B [Member] \| Private Placement Debt [Member]
Debt Instrument [Line Items]
Principal amount	$ 100,000,000	100,000,000
Interest rate	2.90%
Maturity date	Jul. 28, 2026
Senior Notes Due June 11, 2025 [Member] \| Private Placement Debt [Member]
Debt Instrument [Line Items]
Principal amount	$ 20,000,000	20,000,000
Interest rate	3.79%
Maturity date	Jun. 11, 2025
Senior notes, Due March 5, 2027 [Member] \| Private Placement Debt [Member]
Debt Instrument [Line Items]
Principal amount	$ 50,000,000	50,000,000
Interest rate	2.60%
Maturity date	Mar. 05, 2027
Senior notes due January 12, 2023 [Member] \| Private Placement Debt [Member]
Debt Instrument [Line Items]
Principal amount	$ 50,000,000	50,000,000
Interest rate	3.04%
Maturity date	Jan. 12, 2023
Series 2018B notes, due June 11, 2021 [Member] \| Private Placement Debt [Member]
Debt Instrument [Line Items]
Principal amount	$ 20,000,000	20,000,000
Current maturities of long-term debt	$ 20,000,000	20,000,000
Interest rate	3.42%
Maturity date	Jun. 11, 2021
Series 2019A notes, due March 5, 2024 [Member] \| Private Placement Debt [Member]
Debt Instrument [Line Items]
Principal amount	$ 50,000,000	$ 50,000,000
Interest rate	2.40%
Maturity date	Mar. 05, 2024

Interest free short-term borrowings.

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Financing obligations, current

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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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Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

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

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Present value of lessee's discounted obligation for lease payments from finance lease.

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Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

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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 long-term debt and lease obligation, classified as noncurrent.

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Amount of long-term debt and lease obligation, classified as current.

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Amount of long-term debt and lease obligation, including portion classified as current.

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