Income Taxes (Tables)
 6 Months Ended
Feb. 28, 2022
Income Tax Disclosure [Abstract]  
Summary of U.S. Federal Statutory Income Tax Rate Compared to Actual Income Tax Expense The U.S. federal statutory income tax rate and the Company's effective income tax rate are as follows:
Three months ended Six months ended
February 28, 2022 February 28, 2021 February 28, 2022 February 28, 2021
U.S. federal statutory income tax rate 21.0  % 21.0  % 21.0  % 21.0  %
Effective income tax rate 21.7  % 26.9  % 22.8  % 28.5  %