Debt And Capital Lease Obligations (Private Placement Debt) (Narrative) (Details) - Private Placement Debt [Member] - USD ($)	6 Months Ended
Mar. 02, 2019	Sep. 01, 2018
Senior Notes Series A [Member]
Debt Instrument [Line Items]
Principal amount	$ 75,000,000	$ 75,000,000
Interest rate	2.65%	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%	2.90%
Maturity date	Jul. 28, 2026
Senior Notes Due June 11, 2025 [Member]
Debt Instrument [Line Items]
Principal amount	$ 20,000,000	$ 20,000,000
Interest rate	3.79%
Maturity date	Jun. 11, 2025

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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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-Section 55
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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

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+ References

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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/disclosureRef
-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

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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