XML 62 R44.htm IDEA: XBRL DOCUMENT v3.19.2
Short-Term Investments (Tables)
12 Months Ended
May 31, 2019
Investments, Debt and Equity Securities [Abstract]  
Summary of Short-Term Investments
Short-term investments consisted of the following:
 
  As of May 31, 
  2018  2019 
  US$  US$ 
Held-to-maturity
investments
  1,623,763   1,668,689