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Composition Of Certain Financial Statement Captions (Schedule Of Amortized Cost And Estimated Fair Value Of Short-Term And Long-Term Available-For-Sale Investments Based On Stated Maturities) (Details) (USD $) In Thousands | Sep. 30, 2011 | Sep. 24, 2010
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Composition Of Certain Financial Statement Captions [Abstract] |  |
Amortized Cost, due within 1 year | $ 390,559 | $ 289,082
Amortized Cost, due in 1 to 2 years | 213,487 | 183,130
Amortized Cost, due in 2 to 3 years | 58,947 | 18,301
Amortized Cost, total | 662,993 | 490,513
Fair Value, due within 1 year | 391,281 | 289,755
Fair Value, due in 1 to 2 years | 213,921 | 184,891
Fair Value, due in 2 to 3 years | 58,876 | 18,460
Fair Value, total | $ 664,078 | $ 493,106

X
- Definition This item represents debt securities, at cost, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments, as defined), and fair value hedge accounting adjustments, if any, which are expected to mature after one year and through Two years from the balance sheet date and which are categorized neither as held-to-maturity nor trading securities. + Details
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- Definition This item represents the total of all debt securities grouped by maturity dates, at cost, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments, as defined), and fair value hedge accounting adjustments, if any, which are classified neither as held-to-maturity nor trading securities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name FASB Staff Position (FSP) -Number FAS115-1/124-1 -Paragraph 7 -Footnote 2 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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FASB -Name Statement of Financial Accounting Standard (FAS) -Number 115 -Paragraph 20 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.2) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
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