Debt And Capital Lease Obligations (Private Placement Debt) (Narrative) (Details) - Private Placement Debt [Member]	12 Months Ended
Sep. 02, 2017 USD ($)	Sep. 03, 2016 USD ($)
Debt Instrument [Line Items]
Maximum consolidated leverage ratio of total indebtedness to EBITDA	3.00
Maximum consolidated leverage ratio of total indebtedness to EBITDA after material acquisition	3.50
Minimum consolidated interest coverage ratio of EBITDA to total interest expense	3.00
Senior Notes Series A [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]
Debt Instrument [Line Items]
Principal amount	$ 100,000,000	$ 100,000,000
Interest rate	2.90%
Maturity date	Jul. 28, 2026

Maximum Consolidated Leverage Ratio To Indebtedness

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- Definition

Maximum Consolidated Leverage Ratio To Indebtedness after material acquisition

+ References

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- Definition

Minimum Consolidated Interest Coverage Ratio Of Ebitda To Interest Expense

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 55
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=64930739&loc=d3e28878-108400

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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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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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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