Note 12 - Contingent Consideration Liability (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Nov. 30, 2015	May. 31, 2015
Balance at the beginning of the period	$ (18,596)	$ (11,300)
Additions due to acquisitions		(6,469)
Payments	$ (39)	(87)
Accretion of fair value	(570)	(914)
Balance at the end of the period	$ (19,127)	$ (18,596)