Annual report pursuant to Section 13 and 15(d)

Stocks Plans - Additional Information (Detail)

v3.21.2
Stocks Plans - Additional Information (Detail) - USD ($)
$ in Thousands
1 Months Ended 12 Months Ended
Sep. 30, 2020
Aug. 31, 2021
Aug. 31, 2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Class A Common Stock were authorized for issuance   7,825,000  
Common Stock Registered to Cover Shares that Become Issuable   1,800,000  
Shares available for future grants   5,177,996  
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   $ 12,700  
Unrecognized compensation cost related to share-based compensation for stock options and restricted stock outstanding, recognition period   1 year 9 months 18 days  
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized   3,500,000  
Domestic Plan Member      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Defined Benefit Plan, Plan Assets, Benefits Paid $ 600 $ 2,920 $ 3,222
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   $ 9,700 $ 18,200
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