Unrecognized cost of unvested share-based compensation awards.

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

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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

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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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-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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Balance Type:	na
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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

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

+ References

No definition available.

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Stock-Based Compensation - Additional Information (Detail) - USD ($) $ in Millions	3 Months Ended	9 Months Ended
	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2016
Immediately vested common stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)		37,140	35,000
Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)		800,500	126,000
Unrecognized compensation cost for unvested employee stock-based compensation awards outstanding, net of forfeitures	$ 2.8	$ 2.8
Weighted-average period over which unrecognized compensation expense is expected to be recognized		2 years
Restricted stock units (RSUs)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Grants in period (in shares)		16,667
Vesting period		8 days
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period			2 years
Unrecognized compensation cost for unvested employee stock-based compensation awards outstanding, net of forfeitures	$ 0.3	$ 0.3
Weighted-average period over which unrecognized compensation expense is expected to be recognized		1 year 2 months
Options granted in period (in shares)	0	0	9,703
Minimum \| Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		2 years	2 years
Maximum \| Restricted stock awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period		3 years	3 years