Consolidated Statements of Comprehensive Loss - USD ($) $ in Thousands	12 Months Ended
	May 31, 2017	May 31, 2016	May 31, 2015
Statement of Comprehensive Income [Abstract]
Net loss	$ (5,653)	$ (6,785)	$ (6,647)
Other comprehensive income (loss), net of tax: Foreign currency translation income loss	13	4	(254)
Total comprehensive loss	(5,640)	(6,781)	(6,901)
Less: Comprehensive income (loss) attributable to noncontrolling interest	1	(2)	3
Comprehensive loss, attributable to Aehr Test Systems	$ (5,641)	$ (6,779)	$ (6,904)