Stock Options - Schedule of Option Activity (Details) - USD ($)	12 Months Ended
May 31, 2020	May 31, 2019
Stock Options - Schedule Of Option Activity
Number of Options Outstanding, Beginning Balance	200,000
Number of Options Outstanding, Exercised
Number of Options Outstanding, Ending Balance	200,000	200,000
Number of Options Exercisable, Ending Balance	200,000
Number of Options Non-vested, Ending Balance	0
Weighted Average Exercise Price Outstanding, Beginning Balance	$ 0.12
Weighted Average Exercise Price Outstanding, Exercised
Weighted Average Exercise Price Outstanding, Ending Balance	0.12	$ 0.12
Weighted Average Exercise Price, Exercisable	$ 0.12
Remaining Contractual Life (years), Outstanding	2 years
Remaining Contractual Life (years), Exercisable	2 years
Intrinsic Value, Options Exercisable, Ending Balance	$ 82,000

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

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Amount of difference between fair value of the underlying shares reserved for issuance and exercise price of vested portions of options outstanding and currently exercisable.

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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Number of non-vested options outstanding.

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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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