Note 5 - Property And Equipment (Details) - Property And Equipment (USD $) In Thousands, unless otherwise specified	Aug. 31, 2013	May 31, 2013
Property, Plant and Equipment [Line Items]
Property and Equipment	$ 110,634	$ 107,314
Less accumulated depreciation	(35,294)	(30,933)
Property and equipment, net	75,340	76,381
Land [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment	297	301
Building Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment	2,527	2,575
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment	20,649	20,629
Construction in Progress [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment	5,198	5,047
Furniture and Fixtures [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment	3,319	3,282
Machinery and Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and Equipment	$ 78,644	$ 75,480