Note 15 - Segment and Geographic Information - Long-lived Assets by Geographic Area (Details) - USD ($) $ in Thousands		Feb. 28, 2017	May 31, 2016
Long-lived assets (excluding goodwill and intangibles) by geography:
Non-current Assets		$ 76,792	$ 76,015
Concentration of net assets by geography:
Assets, net		310,427	344,546
UNITED STATES
Long-lived assets (excluding goodwill and intangibles) by geography:
Non-current Assets		55,308	55,080
Concentration of net assets by geography:
Assets, net		175,891	200,226
Europe [Member]
Long-lived assets (excluding goodwill and intangibles) by geography:
Non-current Assets	[1]	15,292	14,729
Concentration of net assets by geography:
Assets, net		93,221	102,593
CANADA
Long-lived assets (excluding goodwill and intangibles) by geography:
Non-current Assets		3,536	3,543
Concentration of net assets by geography:
Assets, net		29,821	28,617
Other Georgraphic Area [Member]
Long-lived assets (excluding goodwill and intangibles) by geography:
Non-current Assets	[2]	2,656	2,663
Concentration of net assets by geography:
Assets, net	[2]	$ 11,494	$ 13,110

[1] Long-lived assets located in any individual country within Europe were not material to the Company's consolidated long-lived assets.

[2] Primarily Japan and India.