2. STOCK-BASED COMPENSATION - Options and RSU transactions (Details 2) - Stock Option and RSU Transactions - shares	3 Months Ended		6 Months Ended
	Nov. 30, 2016	Aug. 31, 2016	Nov. 30, 2016
Available Shares, Beginning (in thousands)	1,437	1,847	1,847
Additional shares reserved (in thousands)	2,238
Options granted (in thousands)	(50)	(318)
RSUs granted (in thousands)	0	(138)
Shares cancelled (in thousands)	1	46
2006 Plan available shares expired (in thousands)	(1,438)
Available Shares, Ending (in thousands)	2,188	1,437	2,188