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The annual increment in number of shares in accordance with the number of shares authorized under the plan.

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The threshold percentage of annual increment in the number shares authorized under the plan.

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Monetary value of common stock allocated to investors to buy shares of a new issue of common stock before they are offered to the public. When stock is sold on a subscription basis, the issuer does not initially receive the total proceeds. In general, the issuer does not issue the shares to the investor until it receives the entire proceeds.

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Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Unrecognized cost of unvested options awarded to employees as compensation.

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The cash inflow from the additional capital contribution to the entity.

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Cash received on stock transaction after deduction of issuance costs.

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No definition available.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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Amount of accumulated difference between fair value of underlying shares on dates of exercise and exercise price on options exercised (or share units converted) into shares.

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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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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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The floor of a customized range of exercise prices for purposes of disclosing shares potentially issuable under outstanding stock option awards on all stock option plans and other required information pertaining to awards in the customized range.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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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Purchase price of common stock expressed as a percentage of its fair value.

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

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SHAREHOLDERS` EQUITY (Details) - USD ($)	3 Months Ended	12 Months Ended
SHAREHOLDERS` EQUITY (Details) - USD ($)	Aug. 29, 2018	May 31, 2018	May 31, 2017	Jun. 04, 2018
SHAREHOLDERS` EQUITY (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value (in Dollars per share)		$ 3.63	$ 1.55
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period, Intrinsic Value		$ 87,000	$ 616,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Outstanding, Intrinsic Value		2,755,000	1,354,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Intrinsic Value		1,749,000	$ 616,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Not yet Recognized, Stock Options		$ 212,000
Employee Service Share-based Compensation, Nonvested Awards, Compensation Cost Not yet Recognized, Period for Recognition		1 year 299 days
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercisable, Weighted Average Remaining Contractual Term		5 years 3 months
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period (in Shares)		34,750	341,500
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Lower Range Limit (in Dollars per share)		$ 0.71	$ 0.43
Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range, Upper Range Limit (in Dollars per share)		$ 1.04	$ 1.04
Proceeds from Stock Options Exercised		$ 27,436	$ 157,728
Proceeds from Issuance of Common Stock		$ 1,266,871
Common Stock [Member]
SHAREHOLDERS` EQUITY (Details) [Line Items]
Sale of Stock, Number of Shares Issued in Transaction (in Shares)		342,088
Proceeds from Issuance of Common Stock		$ 1,379,226
Sale of Stock, Consideration Received on Transaction		$ 1,275,933
Common Stock [Member] \| Subsequent Event [Member]
SHAREHOLDERS` EQUITY (Details) [Line Items]
Sale of Stock, Number of Shares Issued in Transaction (in Shares)	44,321
Sale of Stock, Consideration Received on Transaction	$ 170,958
Common Stock, Value, Subscriptions				$ 9,062
Common Stock [Member] \| Minimum [Member]
SHAREHOLDERS` EQUITY (Details) [Line Items]
Sale of Stock, Price Per Share (in Dollars per share)		$ 3.73
Common Stock [Member] \| Minimum [Member] \| Subsequent Event [Member]
SHAREHOLDERS` EQUITY (Details) [Line Items]
Sale of Stock, Price Per Share (in Dollars per share)	$ 3.84
Common Stock [Member] \| Maximum [Member]
SHAREHOLDERS` EQUITY (Details) [Line Items]
Sale of Stock, Price Per Share (in Dollars per share)		$ 4.74
Common Stock [Member] \| Maximum [Member] \| Subsequent Event [Member]
SHAREHOLDERS` EQUITY (Details) [Line Items]
Sale of Stock, Price Per Share (in Dollars per share)	$ 4.16
1999 Plan [Member]
SHAREHOLDERS` EQUITY (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in Shares)		1,000,000
Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized Annual Increment Threshold Percentage		1.50%
Share Based Compensation Arrangement By Share Based Payment Award Number Of Shares Authorized Annual Increment Threshold Number (in Shares)		500,000
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent		80.00%
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period		10 years
2010 Plan [Member]
SHAREHOLDERS` EQUITY (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in Shares)		850,000
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent		80.00%
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period		10 years
2014 Plan [Member]
SHAREHOLDERS` EQUITY (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in Shares)		850,000
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent		80.00%
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period		10 years
2017 Plan [Member]
SHAREHOLDERS` EQUITY (Details) [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized (in Shares)		900,000
Share-based Compensation Arrangement by Share-based Payment Award, Purchase Price of Common Stock, Percent		80.00%
Share-based Compensation Arrangement by Share-based Payment Award, Expiration Period		10 years