Earnings Per Share - Denominator for Calculation of Income (Loss) Per Share (Detail) - shares	12 Months Ended
Apr. 30, 2018	Apr. 30, 2017
Weighted average ordinary shares and adjusted weighted average ordinary shares [abstract]
Issued common share, beginning of year	49,146,851	49,146,851
Weighted average issuances	73,973
Basic weighted average common shares	49,220,824	49,146,851
Effect of dilutive warrants and options	0	0
Diluted weighted average common shares	49,220,824	49,146,851

The weighted average number of ordinary shares outstanding plus the weighted average number of ordinary shares that would be issued on the conversion of all the dilutive potential ordinary shares into ordinary shares. [Refer: Ordinary shares [member]; Weighted average [member]]

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The number of dilutive potential ordinary shares that relate to the assumed exercise of the entity's share options.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-Number 33
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- Definition

The increase (decrease) in the number of shares outstanding. [Refer: Number of shares outstanding]

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition

The number of shares issued by the entity.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The number of ordinary shares outstanding at the beginning of the period, adjusted by the number of ordinary shares bought back or issued during the period multiplied by a time-weighting factor.

+ References

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