7. INCOME TAXES (Details 4) - USD ($) $ in Thousands	12 Months Ended
May 31, 2021	May 31, 2020	May 31, 2019
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefit, beginning	$ 1,852	$ 1,809	$ 1,785
Decreases related to prior year tax positions		(11)	(41)
Increases related to prior year tax positions	11
Increases related to current year tax positions	65	54	65
Unrecognized tax benefit, ending	$ 1,928	$ 1,852	$ 1,809

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

No definition available.

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Amount of unrecognized tax benefits.

+ References

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Amount of increase in unrecognized tax benefits resulting from tax positions that have been or will be taken in current period tax return.

+ References

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Amount of increase in unrecognized tax benefits resulting from tax positions taken in prior period tax returns.

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