The Company and Its Significant Accounting Policies (Details) (USD $) In Millions, except Share data, unless otherwise specified	12 Months Ended
Sep. 25, 2011	Sep. 26, 2010	Sep. 27, 2009
Notes to Financial Statements [Abstract]
Number of weeks in a fiscal period	52 weeks	52 weeks	52 weeks
Securities Lending [Abstract]
Marketable securities loaned under the Company's securities lending program	$ 44	$ 0
Collateral received for marketable securities loaned	46
Derivatives [Abstract]
Foreign currency option contracts recorded in other current assets	17	4
Foreign currency option contracts recorded in other current liabilities	42	19
Foreign currency forward contracts recorded in other current assets	7
Foreign currency put option contracts derivative liabilities at fair value	80	0	0
Revenue Recognition [Abstract]
Revenues from services	less than 10%
License fees recognized over estimated period of license benefit, duration	5 to 15 years
Share-Based Compensation [Abstract]
Weighted-average estimated fair value of employee stock options granted, per share	$ 13.17	$ 12.40	$ 14.27
Period during which the term structure of volatility is used (in years)	2
Expected life of employee stock options granted, in years	5.6	5.5	5.6
Weighted-average estimated fair values of employee RSUs granted, per share	$ 50.14	$ 35.61	$ 0.00
Pre-vesting forfeiture rate	3.00%	3.00%
Share-based compensation expense related to share-based award granted in those periods	165	119	106
Incremental tax benefit from stock options exercised	183	45	79
Foreign Currency [Abstract]
Foreign currency transaction losses	8	6
Income Tax Uncertainties [Abstract]
Income tax uncertainties, minimum likelihood percentage of being realized upon settlement	50.00%
Incremental Dilutive Common Share Equivalents [Abstract]
Incremental dilutive common share equivalents	32,908,000	15,652,000	16,900,000
Accumulated Other Comprehensive Income (Loss), Net of Tax [Abstract]
Accumulated other-than-temporary losses on marketable debt securities related to factors other than credit, net of income taxes	13
Comprehensive Income [Abstract]
Noncredit other-than-temporary impairment losses and subsequent changes in fair value related to certain marketable debt securities, income tax effect	10	(5)	12
Net unrealized (losses) gains on other marketable securities and derivative instruments, income tax effect	80	74	(5)
Reclassification of net realized gains on marketable securities and derivative instruments included in net income, income tax effect	112	(12)	75
Reclassification of other-than-temporary losses on marketable securities included in net income, income tax effect	$ 14	$ (5)	$ 130

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Reclassification adjustment for other-than-temporary losses on marketable securities include in net income, income taxes

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Reductions in the entity's income taxes that arise when compensation cost (from non-qualified share-based compensation) recognized on the entity's tax return exceeds compensation cost from equity-based compensation recognized in financial statements. This element represents the cash inflow reported in the enterprise's financing activities.

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Disclosure of accounting policy for determining an entity's fiscal year or other fiscal period. This disclosure may include identification of the fiscal period end-date, the length of the fiscal period, any reporting period lag between the entity and its subsidiaries, or equity investees. If a reporting lag exists, the closing date of the entity having a different period end is generally noted, along with an explanation of the necessity for using different closing dates. Any intervening events that materially affect the entity's financial position or results of operations are generally also disclosed.

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The aggregate foreign currency transaction gain (loss) (both realized and unrealized) included in determining net income for the reporting period. Excludes foreign currency transactions designated as hedges of net investment in a foreign entity and intercompany foreign currency transactions that are of a long-term nature, when the entities to the transaction are consolidated, combined, or accounted for by the equity method in the reporting enterprise's financial statements. For certain enterprises, primarily banks, that are dealers in foreign exchange, foreign currency transaction gains (losses) may be disclosed as dealer gains (losses).

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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