v2.3.0.15

Composition Of Certain Financial Statement Captions (Schedule Of Investment Portfolio Recorded As Cash Equivalents, Short-Term Investments, And Long-Term Investments) (Details) (USD $) In Thousands	Sep. 30, 2011	Sep. 24, 2010
Investment Holdings [Line Items]
Cost	$ 820,030	$ 879,935
Unrealized Gain	1,632	2,621
Unrealized Loss	(546)	(29)
Estimated Fair Value	821,116	882,527
Corporate Bonds [Member]
Investment Holdings [Line Items]
Cost	177,129	29,238
Unrealized Gain	316	420
Unrealized Loss	(487)
Estimated Fair Value	176,958	29,658
Commercial Paper [Member]
Investment Holdings [Line Items]
Cost		29,983
Estimated Fair Value		29,983
Municipal Debt Securities [Member]
Investment Holdings [Line Items]
Cost	471,005	318,825
Unrealized Gain	1,251	1,781
Unrealized Loss	(55)	(25)
Estimated Fair Value	472,201	320,581
U.S. Agency Securities [Member]
Investment Holdings [Line Items]
Cost	29,858	107,512
Unrealized Gain	65	390
Unrealized Loss	(4)	(4)
Estimated Fair Value	29,919	107,898
U.S. Government Bonds [Member]
Investment Holdings [Line Items]
Cost		39,949
Unrealized Gain		30
Estimated Fair Value		39,979
Money Market Funds [Member]
Investment Holdings [Line Items]
Cost	142,038	354,428
Estimated Fair Value	$ 142,038	$ 354,428

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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.

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Cost of the investment.

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Value of the investment at close of period. For schedules of investments that are categorized, the value would be aggregated by category. For investment in and advances to affiliates, if operations of any controlled companies are different in character from those of the company, group such affiliates within divisions and by type of activities.

+ References

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

-Publisher SEC

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-Article 12

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+ References

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-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-INV

-Section Glossary

-IssueDate 2008-05-01

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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+ References

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-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-INV

-Section Glossary

-IssueDate 2008-05-01

-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.

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