7. INCOME TAXES (Details 4) - USD ($) $ in Thousands	12 Months Ended
May 31, 2020	May 31, 2019	May 31, 2018
Reconciliation of Unrecognized Tax Benefits, Excluding Amounts Pertaining to Examined Tax Returns [Roll Forward]
Unrecognized tax benefit, beginning	$ 1,809	$ 1,785	$ 789
Decreases related to prior year tax positions	(11)	(41)
Increases related to prior year tax positions			889
Increases related to current year tax positions	54	65	107
Unrecognized tax benefit, ending	$ 1,852	$ 1,809	$ 1,785

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.

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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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