Net Income (Loss) Per Share - Reconciliation of Basic and Diluted Share Amounts (Detail) - shares shares in Thousands	3 Months Ended
Dec. 28, 2019	Dec. 29, 2018
Earnings Per Share [Line Items]
Basic weighted average common shares outstanding	267,893	270,590
Weighted average common stock equivalents from assumed exercise of stock options and issuance of stock units	1,828	1,782
Diluted weighted average common shares outstanding	269,721	272,372
Outstanding Stock Options and stock units
Weighted-average anti-dilutive shares related to:
Weighted-average anti-dilutive shares (in shares)	1,290	3,339
Restricted stock units
Weighted-average anti-dilutive shares related to:
Weighted-average anti-dilutive shares (in shares)	1	4

Earnings Per Share [Line Items]

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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.

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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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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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