1. Summary of Accounting Policies (Details) - Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions	12 Months Ended
Apr. 30, 2019	Apr. 30, 2018
1. Summary of Accounting Policies (Details) - Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Line Items]
Expected volatility	35.00%	35.00%
Dividend yield	0.00%	0.00%
Risk-free interest rate		1.85%
Expected lives	5 years	5 years
Minimum [Member]
1. Summary of Accounting Policies (Details) - Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Line Items]
Risk-free interest rate	2.81%
Maximum [Member]
1. Summary of Accounting Policies (Details) - Schedule of Share-based Payment Award, Stock Options, Valuation Assumptions [Line Items]
Risk-free interest rate	3.07%

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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- Definition

The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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- Definition

The risk-free interest rate assumption that is used in valuing an option on its own shares.

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- Definition

Expected term of award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
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