Share-Based Compensation - Performance Stock Units - Additional Information (Detail) - Performance stock units outstanding [Member] $ / shares in Units, $ in Millions	6 Months Ended
Dec. 31, 2018 USD ($) $ / shares
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%
Closing price of common stock used to calculate Aggregate intrinsic value of stock option outstanding \| $ / shares	$ 37.14
Requisite service period	3 years
Unrecognized share-based compensation cost \| $	$ 9.0
Unrecognized share-based compensation, period for recognition	1 year 2 months 12 days
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%
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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- Definition

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

+ References

No definition available.

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- Definition

Threshold percentage of earnings per share to trigger pay out.

+ References

No definition available.

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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
-Subparagraph (i)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

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

+ References

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- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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.

+ References

No definition available.

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- Definition

Percentage of vesting of share-based compensation awards.

+ References

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-Publisher FASB
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-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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