Annual report pursuant to Section 13 and 15(d)

Summary of Stock Option Activity (Detail)

v3.8.0.1
Summary of Stock Option Activity (Detail)
$ / shares in Units, $ in Millions
 12 Months Ended
Aug. 31, 2017
USD ($)
$ / shares
shares
Number of Stock Option Outstanding  
Beginning Balance | shares 3,478,062
Granted | shares 307,390
Exercised | shares (461,355)
Forfeited | shares (132,467)
Ending Balance | shares 3,191,630
Options exercisable at end of Period | shares 2,340,204
Weighted Average Exercise Price  
Beginning Balance | $ / shares $ 23.96
Granted | $ / shares 26.95
Exercised | $ / shares 21.65
Forfeited | $ / shares 28.34
Ending Balance | $ / shares 24.40
Options exercisable at end of Period | $ / shares $ 24.22
Option Outstanding weighted average remaining term 4 years 9 months 6 days
Option exercisable weighted average remaining term 3 years 7 months 2 days
Stock option, aggregate intrinsic Value | $ $ 5.6
Stock option, aggregate intrinsic Value | $ $ 5.0