CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Class A Nonvoting Common Stock	Class B Voting Common Stock	Common Stock	Additional Paid-in Capital	Retained Earnings	Retained Earnings Class A Nonvoting Common Stock	Retained Earnings Class B Voting Common Stock	Treasury Stock	AOCI Attributable to Parent
Beginning Balances at Jul. 31, 2020	$ 863,072			$ 548	$ 331,761	$ 704,456			$ (107,216)	$ (66,477)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	33,481					33,481
Other Comprehensive Income (Loss), Net of Tax	(3,191)									(3,191)
Issuance of shares of Class A Common Stock under stock plan	2,456				3,246				790
Tax benefit and withholdings from deferred compensation distributions	32				32
Stock-based compensation expense	3,574				3,574
Repurchase of shares of Class A Common Stock	(2,720)								2,720
Dividends, Common Stock, Cash		$ 10,671	$ 720				$ 10,671	$ 720
Ending Balances at Oct. 31, 2020	880,401			548	332,121	726,546			(109,146)	(69,668)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared							$ 0.2200	$ 0.2034
Beginning Balances at Jul. 31, 2021	963,028			548	339,125	788,369			(109,061)	(55,953)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net income	35,046
Other Comprehensive Income (Loss), Net of Tax	(4,718)									(4,718)
Issuance of shares of Class A Common Stock under stock plan	3,188				3,187				(1)
Tax benefit and withholdings from deferred compensation distributions	115				115
Stock-based compensation expense	4,129				4,129
Repurchase of shares of Class A Common Stock	(18,924)								18,924
Dividends, Common Stock, Cash		$ 10,858	$ 737				$ 10,858	$ 737
Ending Balances at Oct. 31, 2021	$ 963,893			$ 548	$ 340,182	$ 811,820			$ (127,986)	$ (60,671)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Dividends, Per Share, Declared							$ 0.2250	$ 0.2084