EMPLOYEE STOCK PLANS - Fair Value with Weighted Average Assumptions (Detail) - $ / shares	3 Months Ended	9 Months Ended
Jun. 29, 2018	Jun. 30, 2017	Jun. 29, 2018	Jun. 30, 2017
Employee Stock Purchase Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	6 months	6 months	6 months	6 months
Risk-free interest rate	2.00%	1.00%	1.60%	0.70%
Expected volatility	32.90%	18.20%	25.20%	20.30%
Expected dividend	0.00%	0.00%	0.00%	0.00%
Weighted average fair value at grant date (dollars per share)	$ 28.41	$ 18.42	$ 24.56	$ 18.92
Employee Stock Option Plans
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Expected term (in years)	3 years 10 months 6 days	3 years 11 months 27 days	3 years 9 months 29 days	3 years 11 months 27 days
Risk-free interest rate	2.80%	1.60%	2.20%	1.70%
Expected volatility	21.00%	17.60%	19.00%	21.30%
Expected dividend	0.00%	0.00%	0.00%	0.00%
Weighted average fair value at grant date (dollars per share)	$ 24.93	$ 15.93	$ 20.82	$ 16.11

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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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

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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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 share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (f)(2)(i)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.D.2)
-URI http://asc.fasb.org/extlink&oid=27013229&loc=d3e301413-122809

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