Net Income per Common Share - Reconciliation of Numerator and Denominator of Basic and Diluted Per Share (Detail) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Apr. 30, 2023	Apr. 30, 2022	Apr. 30, 2023	Apr. 30, 2022
Earnings Per Share [Line Items]
Net income	$ 48,052	$ 40,054	$ 125,479	$ 108,915
Denominator for basic income per share for both Class A and Class B	49,653	51,326	49,755	51,700
Plus: Effect of dilutive equity awards	348	242	278	355
Denominator for diluted income per share for both Class A and Class B	50,001	51,568	50,033	52,055
Class A Nonvoting Common Stock
Earnings Per Share [Line Items]
Basic	$ 0.97	$ 0.78	$ 2.52	$ 2.11
Diluted	$ 0.96	$ 0.78	$ 2.51	$ 2.09
Class B Voting Common Stock
Earnings Per Share [Line Items]
Preferential dividends	$ 0	$ 0	$ 769	$ 803
Preferential dividends on dilutive stock options	0	0	4	(8)
Numerator for basic and diluted income per Class B Voting Common Share	$ 48,052	$ 40,054	$ 124,706	$ 108,104
Basic	$ 0.97	$ 0.78	$ 2.51	$ 2.09
Diluted	$ 0.96	$ 0.78	$ 2.49	$ 2.08