Net Income per Common Share - Additional Informations (Detail) - shares |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Apr. 30, 2020 |
Apr. 30, 2019 |
Apr. 30, 2020 |
Apr. 30, 2019 |
|
| Class A nonvoting common stock | ||||
| Earnings Per Share [Line Items] | ||||
| Common stock of Class A shares excluded from computations of diluted net earnings per share | 488,932 | 269,606 | 353,752 | 407,477 |