XML 60 R35.htm IDEA: XBRL DOCUMENT v3.8.0.1
Product Development Assets (Tables)
12 Months Ended
Apr. 30, 2018
Product Development Assets [Abstract]  
Product Development Assets
Product development assets consisted of the following at April 30:

  
2018
  
2017
 
Book Composition Costs
 
$
24,887
  
$
28,884
 
Other Product Development Costs
  
53,927
   
51,501
 
Total
 
$
78,814
  
$
80,385