Stock-Based Compensation - Weighted-Average Assumptions Utilized to Value Stock Options (Detail) - USD ($)	3 Months Ended
Dec. 28, 2019	Dec. 29, 2018
Share-based Payment Arrangement [Abstract]
Risk-free interest rate	1700000.00%	3.00%
Expected volatility	33.60%	34.30%
Expected life (in years)	4 years 9 months 18 days	4 years 9 months 18 days
Dividend yield	$ 0	$ 0
Weighted average fair value of options granted	$ 13.83	$ 13.41

No definition available.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Disclosure of the weighted average expected dividend for an entity using a valuation technique with different dividend rates during the contractual term.

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- Definition

Rate of weighted-average expected volatility for award under share-based payment arrangement.

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
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-Publisher FASB
-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

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