STOCK-BASED COMPENSATION - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Total intrinsic value of options exercised	$ 11.4	$ 6.2	$ 0.1
Total pre-tax unrecognized compensation costs related to non-vested awards	$ 22.7
Total pre-tax unrecognized compensation costs related to non-vested awards expected to be recognized, years	2 years 4 months 24 days
Total fair value of options and Restricted Stock Units vested	$ 14.8	$ 13.9	$ 21.7
Stock Incentive Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Weighted average estimated grant date fair values, for options granted at market price, per share	$ 14.63	$ 9.09	$ 8.85
Common Stock, Capital Shares Reserved for Future Issuance	8,236,479
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 34.67	$ 23.92	$ 24.41
Restricted Stock Units Outstanding, Shares Granted	516,090
Performance Based Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock Units Outstanding, Shares Granted	246,890
Non-Performance Based Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock Units Outstanding, Shares Granted	269,200

Aggregate number of common shares reserved for future issuance.

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Unrecognized cost of unvested share-based compensation awards.

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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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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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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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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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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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