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, 2026	Apr. 30, 2025	Apr. 30, 2026	Apr. 30, 2025
Earnings Per Share [Line Items]
Net income	$ 57,800	$ 52,263	$ 159,787	$ 139,380
Denominator for basic income per share for both Class A and Class B	47,357	47,644	47,313	47,743
Plus: Effect of dilutive equity awards	457	422	448	453
Denominator for diluted income per share for both Class A and Class B	47,814	48,066	47,761	48,196
Class A Nonvoting Common Stock
Earnings Per Share [Line Items]
Basic	$ 1.22	$ 1.10	$ 3.38	$ 2.92
Diluted	$ 1.21	$ 1.09	$ 3.35	$ 2.89
Class B Voting Common Stock
Earnings Per Share [Line Items]
Preferential dividends	$ 0	$ 0	$ 728	$ 736
Preferential dividends on dilutive stock options	0	0	(8)	(8)
Numerator for basic and diluted income per Class B Voting Common Share	$ 57,800	$ 52,263	$ 159,051	$ 138,636
Basic	$ 1.22	$ 1.10	$ 3.36	$ 2.90
Diluted	$ 1.21	$ 1.09	$ 3.33	$ 2.88