Note 6 - Property and Equipment, Net - Property and Equipment, Net (Details) - USD ($) $ in Thousands	Feb. 28, 2017	May 31, 2016
Property and Equipment, Gross	$ 156,399	$ 146,922
Less: Accumulated depreciation	(79,607)	(70,907)
Property and equipment, net	76,792	76,015
Land [Member]
Property and Equipment, Gross	214	217
Building and Building Improvements [Member]
Property and Equipment, Gross	2,183	2,163
Leasehold Improvements [Member]
Property and Equipment, Gross	26,379	26,261
Construction in Progress [Member]
Property and Equipment, Gross	8,273	4,275
Furniture and Fixtures [Member]
Property and Equipment, Gross	4,219	3,861
Machinery and Equipment [Member]
Property and Equipment, Gross	$ 115,131	$ 110,145

Amount of accumulated depreciation, depletion and amortization for physical assets used in the normal conduct of business to produce goods and services.

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-Name Accounting Standards Codification
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Amount before accumulated depreciation, depletion and amortization of physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, and furniture and fixtures.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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