Share-Based Compensation - Market Stock Units - Additional Information (Detail) - Market stock units outstanding [Member] $ / shares in Units, $ in Millions	12 Months Ended
Jun. 30, 2018 USD ($) $ / shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period of the underlying awards	3 years
Potential payout range	100.00%
Potential payout adjustment ratio	2.00%
Closing price of common stock used to calculate Aggregate intrinsic value of stock option outstanding \| $ / shares	$ 50.37
Unrecognized share-based compensation cost \| $	$ 14.4
Unrecognized share-based compensation, period for recognition	1 year 1 month 13 days
October 2014 MSU Grants [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
SOX Index TSR percentage points	118.00%
Percentage of targeted shares, MSU grants	0.00%
October 2015 MS Grants [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
SOX Index TSR percentage points	115.00%
Percentage of targeted shares, MSU grants	0.00%
October 2016 MSU Grants [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
SOX Index TSR percentage points	60.00%
Percentage of targeted shares, MSU grants	0.00%
Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Potential payout range	0.00%
Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Potential payout range	200.00%
Share-based Compensation Award, First Tranche [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period of the underlying awards	1 year
Share-based Compensation Award, First Tranche [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Potential payout range	100.00%
Share-based Compensation Award, Second Tranche [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period of the underlying awards	2 years
Share-based Compensation Award, Second Tranche [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Potential payout range	100.00%
Share-based Compensation Award, Third Tranche [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period of the underlying awards	3 years

Delivery of targeted shares in percentage delivered by entity.

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- Definition

Percentage of potential payout.

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Potential payout adjustment ratio.

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- Definition

Share based compensation arrangement by share based payment award intrinsic value closing price.

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TSR decrease in percentage points.

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

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

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- Definition

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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- Definition

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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