Summary of Significant Accounting Policies - Reconciliation of Basic and Diluted Share Amounts (Detail) In Thousands, unless otherwise specified	12 Months Ended
Sep. 27, 2014	Sep. 28, 2013	Sep. 29, 2012
Earnings Per Share [Line Items]
Basic weighted average common shares outstanding (in shares)	275,499	268,704	264,041
Weighted Average Common Stock Equivalents From Assumed Exercise Of Stock Options And Restricted Stock Units	2,368	0	0
Incremental shares from assumed conversion of the Convertible Notes premium (in shares)	493	0	0
Diluted weighted average common shares outstanding (in shares)	278,360	268,704	264,041
Outstanding Stock Options [Member]
Weighted-average anti-dilutive shares related to:
Weighted-average anti-dilutive shares (in shares)	5,033	8,445	10,491
Restricted Stock Units [Member]
Weighted-average anti-dilutive shares related to:
Weighted-average anti-dilutive shares (in shares)	20	1,109	1,378

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Weighted average common stock equivalents from assumed exercise of stock options and restricted stock units

+ References

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 260

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (c)

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- Definition

Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the if-converted method.

+ References

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

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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