Annual report pursuant to Section 13 and 15(d)

Summary of Stock Option Activity (Detail)

v3.10.0.1
Summary of Stock Option Activity (Detail)
$ / shares in Units, $ in Millions
 12 Months Ended
Aug. 31, 2018
USD ($)
$ / shares
shares
Number of Stock Option Outstanding  
Beginning Balance | shares 3,191,630
Granted | shares 0
Exercised | shares (833,377)
Forfeited | shares (119,527)
Expired | shares (469,650)
Ending Balance | shares 1,769,076
Options exercisable at end of Period | shares 1,285,352
Weighted Average Exercise Price  
Beginning Balance | $ / shares $ 24.40
Granted | $ / shares 0.00
Exercised | $ / shares 19.96
Forfeited | $ / shares 23.98
Expired | $ / shares 28.59
Ending Balance | $ / shares 25.40
Options exercisable at end of Period | $ / shares $ 25.52
Option Outstanding weighted average remaining term 4 years 9 months
Option exercisable weighted average remaining term 3 years 9 months
Stock option, aggregate intrinsic Value | $ $ 7.9
Stock option, aggregate intrinsic Value | $ $ 5.9