Stock-Based Awards - Summary of Stock Options, Restricted Stock and Restricted Stock Unit Activity (Detail)	3 Months Ended
Jun. 30, 2018 shares
Stock Options [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options, beginning balance	985,537
Options, Granted	0
Options, Exercised/vested	(10,000)
Options, Forfeitures	0
Options, ending balance	975,537
Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock, beginning balance	2,319,057
Restricted Stock, Granted	173,203
Restricted Stock, Exercised/vested	(145,383)
Restricted Stock, Forfeitures	(14,931)
Restricted Stock, ending balance	2,331,946
Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Restricted Stock, beginning balance	12,096
Restricted Stock, ending balance	12,096

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

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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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No definition available.

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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

No definition available.

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

+ References

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-Topic 718
-SubTopic 10
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- Definition

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

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