Debt And Capital Lease Obligations (Private Placement Debt) (Narrative) (Details) - Private Placement Debt [Member]	3 Months Ended	12 Months Ended
Dec. 03, 2016 USD ($)	Sep. 03, 2016 USD ($)
Debt Instrument [Line Items]
Maximum consolidated leverage ratio of total indebtedness to EBITDA	3.00
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%	2.65%
Maturity date	Jul. 28, 2023	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	Jul. 28, 2026

Maximum Consolidated Leverage Ratio To Indebtedness

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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=34725769&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=6451184&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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- Definition

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.

+ References

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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