Schedule of Stock Option Compensation Expense (Detail) - Predecessor - USD ($) $ / shares in Units, $ in Thousands	4 Months Ended	12 Months Ended
Jul. 31, 2017	Mar. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock option compensation expense	$ 1,644	$ 745
Basic loss per share increased by	$ 0.02	$ 0.02
Diluted loss per share increased by	$ 0.02	$ 0.02

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.

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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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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