Net Income Per Share - Reconciliation of Basic and Diluted Share Amounts (Detail) - shares shares in Thousands	3 Months Ended	6 Months Ended
Mar. 30, 2019	Mar. 31, 2018	Mar. 30, 2019	Mar. 31, 2018
Earnings Per Share [Line Items]
Basic weighted average common shares outstanding	269,235	277,114	269,913	276,985
Weighted average common stock equivalents from assumed exercise of stock options and issuance of stock units	0	0	0	0
Incremental shares from Convertible Notes premium	0	0	0	0
Diluted weighted average common shares outstanding	269,235	277,114	269,913	276,985
Outstanding Stock Options and stock units
Weighted-average anti-dilutive shares related to:
Weighted-average anti-dilutive shares (in shares)	4,031	5,079	4,578	4,890
Convertible Notes Payable [Member]
Weighted-average anti-dilutive shares related to:
Weighted-average anti-dilutive shares (in shares)	0	1,079	0	1,406

Earnings Per Share [Line Items]

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of convertible debt securities using the treasury stock method

+ References

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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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