Aggregate number of common shares reserved for future issuance.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.29)

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Unrecognized cost of unvested share-based compensation awards.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 10

-Section 50

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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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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Name Accounting Standards Codification

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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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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-Publisher FASB

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-Topic 718

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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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-Name Accounting Standards Codification

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STOCK-BASED COMPENSATION - Additional Information (Detail) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended		6 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2014	Dec. 31, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentives granted, vesting period, in years			5 years
Total intrinsic value of options exercised			$ 3.7	$ 1.8
Total pre-tax unrecognized compensation costs related to non-vested awards	28.6		28.6
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 vested	$ 17.5	$ 14.5
Employee Stock Option \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock incentives granted, vesting period, in years			10 years
Stock Incentive Plans
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Capital Shares Reserved for Future Issuance	9,798,238		9,798,238
Restricted Stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock Outstanding, Shares Granted			324,070
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value			$ 43.77	$ 28.32
Performance Based Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock Outstanding, Shares Granted			98,940
Non-Performance Based Shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock Outstanding, Shares Granted			225,130
Stock Options Plan
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			$ 17.94	$ 11.68