7. INCOME TAXES (Details 3) - USD ($) $ in Thousands	May 31, 2018	May 31, 2017
Components of Deferred Tax Assets [Abstract]
Net operating losses	$ 12,918	$ 18,719
Credit carryforwards	4,952	4,715
Inventory reserves	588	870
Reserves and accruals	1,419	1,566
Other	247	393
Gross deferred tax assets	20,124	26,263
Less: Valuation allowance	(20,124)	(26,263)
Net deferred tax assets	$ 0	$ 0

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from inventory.

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