Stockholders' Equity - Schedule of Stock Option Activity (Details)	3 Months Ended
Jul. 31, 2018 $ / shares shares
Equity [Abstract]
Number of Options Outstanding, Beginning of Period \| shares	1,531,458
Number of Options, Granted \| shares
Number of Options, Exercised \| shares
Number of Options, Forfeited \| shares
Number of Options, Cancelled \| shares	(50,000)
Number of Options Outstanding, End of Period \| shares	1,481,458
Number of Options exercisable at end of period \| shares	593,958
Number of Options expected to vest \| shares	887,500
Weighted Average Exercise Price Outstanding, Beginning of Period	$ 1.79
Weighted Average Exercise Price, Granted
Weighted Average Exercise Price, Exercised
Weighted Average Exercise Price, Forfeited
Weighted Average Exercise Price, Cancelled	1.47
Weighted Average Exercise Price Outstanding, End of Period	1.80
Weighted Average Exercise Price Options exercisable at end of period	2.30
Weighted Average Exercise Price Options expected to vest	1.47
Weighted Average Exercise Price Weighted average fair value of options granted during the period
Weighted Average Remaining Contractual Life (Years), Beginning of Period	4 years 5 months 5 days
Weighted Average Remaining Contractual Life (Years), Ending of Period	4 years 2 months 1 day

Share based compensation arrangement by share based payment award options cancelled in period.

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Share based compensation arrangements by share based payment award options cancelled in period weighted average exercise price.

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Sharebased compensation arrangement by sharebased payment award options outstanding weighted average remaining contractual term.

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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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

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The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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Number of options outstanding, including both vested and non-vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. 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.

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Weighted-average exercise price, at which grantee can acquire shares reserved for issuance, for fully vested and expected to vest options outstanding. 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.

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Weighted average price at which option holders acquired shares when converting their stock options into shares.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

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Weighted average remaining contractual term for option awards outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of share options (or share units) exercised during the current period.

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