Note 5 - Property and Equipment (Details) - Property And Equipment (USD $) In Thousands, unless otherwise specified	Feb. 28, 2014	May 31, 2013
Property, Plant and Equipment [Line Items]
Property and Equipment	$ 119,371	$ 107,314
Less accumulated depreciation	(43,409)	(30,933)
Property and equipment, net	75,962	76,381
Land [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment	286	301
Building Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment	2,891	3,034
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment	20,461	20,170
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment	6,791	5,139
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment	3,618	3,282
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment	$ 85,324	$ 75,388