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Stock Purchase And Stock Option Plans (Stock Issuance Activity Under The 1989 ESPP And The GESPP) (Details) (USD $)	12 Months Ended
	Sep. 30, 2011	Oct. 01, 2010	Oct. 02, 2009
Aggregate Purchase Price Paid for Shares Sold	$ 34,781,962	$ 32,892,633	$ 40,279,536
Aggregate Number of Shares Sold	841,204	877,356	1,042,661
Discount available to employees on the purchase of common stock	5.00%
Common Stock, Capital Shares Reserved for Future Issuance	8,712,242
Under The 1989 ESPP [Member]
Aggregate Purchase Price Paid for Shares Sold	31,887,660	30,042,431	37,246,390
Aggregate Number of Shares Sold	771,818	802,508	966,241
Common Stock, Capital Shares Reserved for Future Issuance	3,910,515
Under The GESPP [Member]
Aggregate Purchase Price Paid for Shares Sold	$ 2,894,302	$ 2,850,202	$ 3,033,146
Aggregate Number of Shares Sold	69,386	74,848	76,420
Common Stock, Capital Shares Reserved for Future Issuance	413,391

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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 129

-Paragraph 4

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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