Share-Based Compensation - Summary of Share Option Activity (Detail) - $ / shares	3 Months Ended	12 Months Ended
Jun. 30, 2019	Mar. 31, 2019
Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]
Number of Share Options Outstanding, Beginning Balance	1,936,397
Number of Share Options Outstanding, Exercised	(9,889)
Number of Share Options Outstanding, Forfeited	(12,176)
Number of Share Options Outstanding, Ending Balance	1,914,332	1,936,397
Number of Share Options Outstanding, Exercisable	1,548,630
Weighted-Average Exercise Price, Beginning Balance	$ 7.77
Weighted-Average Exercise Price, Exercised	7.09
Weighted-Average Exercise Price, Forfeited	11.69
Weighted-Average Exercise Price, Ending Balance	7.75	$ 7.77
Weighted-Average Exercise Price, Exercisable	$ 8.05
Weighted-Average Remaining Contractual Life, Outstanding	75 months	78 months
Weighted-Average Remaining Contractual Life, Exercisable	68 months

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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