Note 6 - Intangible Assets (Tables)
|3 Months Ended|
Aug. 31, 2017
|Disclosure Text Block [Abstract]|
|Schedule of Finite-Lived Intangible Assets [Table Text Block]||
Intangible assets consisted of the following at August 31, 2017 and May 31, 2017.
Tabular disclosure of assets, excluding financial assets and goodwill, lacking physical substance with a finite life, by either major class or business segment.
Reference 1: http://www.xbrl.org/2003/role/presentationRef