EMPLOYEE STOCK PLANS - Additional Information (Detail) $ in Millions	9 Months Ended
Jun. 28, 2019 USD ($)
Stock options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation expense related to outstanding stock awards	$ 20.2
Weighted average period unrecognized compensation expense is expected to be recognized, years	2 years
Restricted stocks, restricted stock units, deferred stock units and performance units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation expense related to outstanding stock awards	$ 46.1
Weighted average period unrecognized compensation expense is expected to be recognized, years	1 year 10 months 24 days

Amount of cost not yet recognized for nonvested award under share-based payment arrangement.

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 (i)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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- Definition

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