Stock-Based Awards - Summary of Stock Options, Restricted Stock and Restricted Stock Unit Activity (Detail)	3 Months Ended
Sep. 30, 2017 shares
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock, beginning balance	2,241,633
Restricted Stock, Granted	96,598
Restricted Stock, Exercised/vested	(150,454)
Restricted Stock, Forfeitures	(10,948)
Restricted Stock, ending balance	2,176,829
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock, beginning balance	2,276
Restricted Stock, Granted	3,472
Restricted Stock, ending balance	5,748
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, beginning balance	1,325,947
Options, Granted	0
Options, Exercised/vested	(10,370)
Options, Forfeitures	0
Options, ending balance	1,315,577

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

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=96867065&loc=d3e5070-113901

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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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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

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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- Definition

Gross number of share options (or share units) granted during the period.

+ References

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Number of options outstanding, including both vested and non-vested options.

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- Definition

Number of share options (or share units) exercised during the current period.

+ References

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-Name Accounting Standards Codification
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