EMPLOYEE STOCK PLANS - Additional Information (Detail) $ in Millions	9 Months Ended
Jun. 30, 2017 USD ($) shares
Stock options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Unrecognized compensation expense related to outstanding stock awards \| $	$ 11.9
Weighted average period unrecognized compensation expense is expected to be recognized, years	1 year 10 months 24 days
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 \| $	$ 37.9
Weighted average period unrecognized compensation expense is expected to be recognized, years	1 year 10 months 24 days
Third Amended and Restated 2005 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares counted against the available for grant (in shares)	2.6
Third Amended and Restated 2005 Plan \| Stock options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares counted against the available for grant (in shares)	1
Beginning Fiscal Year 2016 \| Third Amended 2005 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Ratio of maximum payout (in shares)	1.75
Beginning In Fiscal 2015 \| Third Amended 2005 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Ratio of maximum payout (in shares)	2.0
Before Fiscal Year 2015 \| Third Amended 2005 Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Ratio of maximum payout (in shares)	1.5

Unrecognized cost of unvested share-based compensation awards.

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

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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