Share-Based Compensation - Performance Stock Units - Additional Information (Detail) $ in Millions	12 Months Ended
Jun. 30, 2018 USD ($) shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock units, granted	300,071
Performance stock units outstanding [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period of the underlying awards	3 years
Vesting percentage of the underlying awards	33.33%
Stock units, granted	315,380
Stock units, delivered	0
Stock units, forfeited	20,839
Aggregate intrinsic value \| $	$ 14.8
Requisite service period	3 years
Unrecognized share-based compensation cost \| $	$ 7.7
Unrecognized share-based compensation, period for recognition	1 year 5 months 1 day
Performance stock units outstanding [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Potential payout range	0.00%
Threshold percentage of earnings per share to trigger pay out	65.00%
Performance stock units outstanding [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Potential payout range	200.00%
Threshold percentage of earnings per share to trigger pay out	135.00%

Percentage of potential payout.

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Threshold percentage of earnings per share to trigger pay out.

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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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Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, 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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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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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 number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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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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Percentage of vesting of share-based compensation awards.

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Intrinsic value of equity-based compensation awards outstanding. Excludes stock and unit options.

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