Risk free rate description.

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- Definition

Share based compensation arrangement by share based payment award, consecutive trading days in which target price must exceed threshold.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment Award, period in which target must be achieved, end date.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award period in which target must be achieved, start date.

+ References

No definition available.

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- Definition

Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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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

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- Definition

Description of award terms as to how many shares or portion of an award are no longer contingent on satisfaction of either a service condition, market condition or a performance condition, thereby giving the employee the legal right to convert the award to shares, to sell the shares, and be entitled to the cash proceeds of such sale. For example, vesting may be expressed as being 25 percent of the shares under option on each anniversary of the grant date.

+ References

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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

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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- Definition

Weighted average remaining contractual term for fully vested and expected to vest options outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

+ References

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Share-Based Compensation - Additional Information (Detail) $ / shares in Units, $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2018 USD ($) $ / shares shares	Dec. 31, 2017 USD ($)	Dec. 31, 2018 USD ($) d $ / shares shares	Dec. 31, 2017 USD ($)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share-based compensation expense \| $	$ 1,073	$ 986	$ 3,576	$ 3,458
Risk-free interest rate, Description			Risk-Free Interest Rate. The risk-free interest rate is based on the US Treasury 10-year bond yield in effect at the time of grant.
Employee Stock Option [Member] \| Minimum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			1 year
Employee Stock Option [Member] \| Maximum [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Vesting period			3 years
Restricted Stock Units (RSUs) [Member] \| Time Based Vesting [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of restricted stock units outstanding	724,772		724,772
Weighted average remaining vesting period			11 months
Restricted Stock Units (RSUs) [Member] \| Milestone Vesting [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of restricted stock units outstanding	254,980		254,980
Multi Year Performance Based Restricted Stock Units [Member] \| Vesting Based on $22 Share Price [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of restricted stock units outstanding	106,000		106,000
Award vesting description			106,000 MRSUs which will vest between April 1, 2019 and December 31, 2019 if the Company’s ordinary share price exceeds $22 for 20 consecutive days in this period.
Consecutive trading days in which price must exceed threshold \| d			20
Period in which the target must be achieved, start date			Apr. 01, 2019
Period in which the target must be achieved, end date			Dec. 31, 2019
Ordinary Shares [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Company's closing share price \| $ / shares	$ 6.12		$ 6.12
Ordinary Shares [Member] \| Multi Year Performance Based Restricted Stock Units [Member] \| Minimum [Member] \| Vesting Based on $22 Share Price [Member]
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Company's closing share price \| $ / shares	$ 22		$ 22