Share Capital - Summary of Changes In Options (Detail)	12 Months Ended
Apr. 30, 2019 Option $ / shares
Disclosure Of Defined Benefit Plans [Abstract]
Beginning balance, shares \| Option	948,750
Expired, shares \| Option	(948,750)
Weighted average exercise price, Outstanding and Exercisable \| $ / shares	$ 0.88
Weighted average exercise price, Forfeited/expired \| $ / shares	$ 0.88

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The number of share options outstanding in a share-based payment arrangement.

+ References

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The number of share options forfeited in a share-based payment arrangement.

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The weighted average exercise price of share options forfeited in a share-based payment arrangement. [Refer: Weighted average [member]]

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The weighted average exercise price of share options outstanding in a share-based payment arrangement. [Refer: Weighted average [member]]

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