Note 3 - Consolidated Variable Interest Entity - Components of Assets and Liabilities of Variable Interest Entities (Details) - USD ($) $ in Thousands	Feb. 28, 2017	May 31, 2016	Feb. 29, 2016	May 31, 2015
Cash and Cash Equivalents, at Carrying Value	$ 10,035	$ 10,263	$ 12,190	$ 18,363
Accounts payable	21,263	22,229
Total current assets	131,850	127,679
Total current liabilities	85,942	75,362
Property and equipment, net	76,792	76,015
Deferred income tax liabilities	201,509	222,357
Goodwill	854,736	857,023		842,258
Business Combination, Contingent Consideration, Liability	43,384	40,356		$ 18,596
Non-current Assets	76,792	76,015
Total assets	1,663,871	1,707,633
Total liabilities	1,353,444	1,363,087
Sentilus [Member]
Cash and Cash Equivalents, at Carrying Value	337	36
Accounts payable	964	744
Total current assets	337	36
Accrued expenses and other current liabilities	12	4
Total current liabilities	976	748
Property and equipment, net	674	644
Deferred income tax liabilities	3,671	6,207
Goodwill	105	105
Other intangible assets, net	18,815	18,820
Business Combination, Contingent Consideration, Liability	8,021	7,433
Non-current Assets	19,594	19,569
Total noncurrent liabilities	11,692	13,640
Total assets	19,931	19,605
Total liabilities	$ 12,668	$ 14,388