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		6 Months Ended
	Jan. 31, 2025	Jan. 31, 2024	Jan. 31, 2025	Jan. 31, 2024
Earnings Per Share [Line Items]
Net income	$ 40,334	$ 43,628	$ 87,117	$ 90,869
Denominator for basic income per share for both Class A and Class B	47,851	48,374	47,792	48,440
Plus: Effect of dilutive equity awards	455	351	469	328
Denominator for diluted income per share for both Class A and Class B	48,306	48,725	48,261	48,768
Class A Nonvoting Common Stock
Earnings Per Share [Line Items]
Basic	$ 0.84	$ 0.90	$ 1.82	$ 1.88
Diluted	$ 0.83	$ 0.90	$ 1.81	$ 1.86
Class B Voting Common Stock
Earnings Per Share [Line Items]
Preferential dividends	$ 0	$ 0	$ 736	$ 748
Preferential dividends on dilutive stock options	0	0	(8)	(5)
Numerator for basic and diluted income per Class B Voting Common Share	$ 40,334	$ 43,628	$ 86,373	$ 90,116
Basic	$ 0.84	$ 0.90	$ 1.81	$ 1.86
Diluted	$ 0.83	$ 0.90	$ 1.79	$ 1.85