Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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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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Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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Unrecognized cost of unvested options awarded to employees as compensation.

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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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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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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of share instruments newly issued under a share-based compensation plan.

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The number of shares purchased on the open market during the period for issuance to employees under the plan.

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Share-Based Compensation - Additional Information (Detail) - USD ($) $ in Millions		1 Months Ended	12 Months Ended
	Dec. 05, 2012	Sep. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2013	Dec. 05, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options exercisable, weighted average remaining contractual life			5 years 3 months
Total unrecognized share-based compensation cost related to stock options			$ 15.7
Share based compensation expense			$ 45.7	$ 34.0	$ 26.6
Shares purchased under the Plan			200,000	200,000	100,000
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period of share-based compensation vested, years			4 years
Total unrecognized share-based compensation cost, weighted-average period, years			1 year 7 months 6 days
Stock options \| Share-based compensation granted after December 5, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expire from date of grant, years			8 years
Stock options \| Share-based compensation granted prior to December 5, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expire from date of grant, years			10 years
Restricted Stock Units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Service period of share-based compensation vested, years		4 years
Total unrecognized share-based compensation cost, weighted-average period, years			2 years 8 months 1 day
Total unrecognized share-based compensation cost related to RSUs			$ 20.8
Unrecognized share-based compensation cost			$ 37.3
1995 Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares approved	2,000,000
Shares issued under the Plan	2,000,000
2012 Purchase Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares approved	2,000,000
Shares purchased under the Plan			400,000
Unrecognized share-based compensation cost			$ 0.8
The 2010 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares approved						3,500,000
Shares reserved for issuance exercise of options			2,200,000
The 2010 Plan \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available for future grant			4,400,000
Chief Financial Officer [Member] \| Resignation Agreement In October Two Thousand Fourteen
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation expense			$ 3.1
Chief Executive Officer [Member] \| Resignation Agreement In February Two Thousand Fifteen [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share based compensation expense			$ 12.8