Note 20 - Long-lived Assets by Geographic Area (Details) - USD ($) $ in Thousands	May 31, 2016	May 31, 2015
UNITED STATES
Long-lived assets (excluding goodwill and intangibles) by geography:
Non-current Assets	$ 55,080	$ 52,764
Concentration of net assets by geography:
Assets, net	200,226	241,522
Europe [Member]
Long-lived assets (excluding goodwill and intangibles) by geography:
Non-current Assets	14,729	14,542
Concentration of net assets by geography:
Assets, net	102,593	100,071
CANADA
Long-lived assets (excluding goodwill and intangibles) by geography:
Non-current Assets	3,543	4,029
Concentration of net assets by geography:
Assets, net	28,617	30,274
Other Georgraphic Area [Member]
Long-lived assets (excluding goodwill and intangibles) by geography:
Non-current Assets	2,663	2,239
Concentration of net assets by geography:
Assets, net	13,110	11,814
Non-current Assets	76,015	73,574
Assets, net	$ 344,546	$ 383,681