Annual report pursuant to Section 13 and 15(d)

Stocks Plans - Additional Information (Detail)

v3.5.0.2
Stocks Plans - Additional Information (Detail) - USD ($)
$ in Millions
12 Months Ended
Aug. 31, 2016
Aug. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Class A Common Stock were authorized for issuance 9,400,000  
Shares available for future grants 1,935,182  
Exercise price as percentage of fair market value at grant date 100.00%  
Unrecognized compensation cost related to share-based compensation for stock options and restricted stock outstanding $ 24.8  
Unrecognized compensation cost related to share-based compensation for stock options and restricted stock outstanding, recognition period 3 years 1 day  
Performance Shares    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Performance period 3 years  
Performance Shares | Free Cash Flow Conversion Target    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage 50.00%  
Performance Shares | Total Shareholders Return    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage 50.00%  
Restricted Stock    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Fair value of shares vested $ 12.4 $ 14.2
After Three Years    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage 50.00%  
After Five Years    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Rights, Percentage 100.00%  
Maximum | Stock Options    
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]    
Stock options term 10 years