Stock-Based Compensation (Expenses) (Details) - USD ($)	12 Months Ended
	Jul. 31, 2025	Jul. 31, 2024	Jul. 31, 2023	Jul. 31, 2022
Stock-based Compensation Expenses
Stock-based compensation expense (benefit) before income tax benefit	$ 3,120,000	$ 6,096,000	$ 10,107,000
CEO transition costs related to equity-classified stock-based awards	0	0	3,764,000
Total stock-based compensation expense before income tax benefit	3,120,000	6,096,000	13,871,000
Estimated income tax benefit	0	(1,298,000)	(2,552,000)
Net stock-based compensation expense	3,120,000	$ 4,798,000	$ 11,319,000
Total remaining unrecognized compensation cost related to the unvested stock-based awards	4,778,000
Estimated forfeitures related to unvested stock-based awards	$ 342,000
Weighted average number of years net compensation cost is expected to be recognized over	1 year 8 months 12 days
Stock-based compensation capitalized and included in ending inventory	$ 198,000
Number of stock-based awards outstanding at period end (in shares)	124,470	141,190	240,510	483,480
Stock options
Stock-based Compensation Expenses
Stock-based compensation expense (benefit) before income tax benefit	$ 29,000	$ 60,000	$ 87,000
Performance shares
Stock-based Compensation Expenses
Stock-based compensation expense (benefit) before income tax benefit	72,000	480,000	973,000
RSUs, restricted stock, share units and other stock-based awards
Stock-based Compensation Expenses
Stock-based compensation expense (benefit) before income tax benefit	2,973,000	5,477,000	8,926,000
ESPP
Stock-based Compensation Expenses
Stock-based compensation expense (benefit) before income tax benefit	$ 46,000	$ 79,000	121,000
Discount offered to employees participating in the ESPP as a percentage of market price	15.00%
2000 Stock Incentive Plan | Stock appreciation rights (SARs)
Stock-based Compensation Expenses
Number of stock-based awards outstanding at period end (in shares)	0	0
2000 Stock Incentive Plan | Stock options
Stock-based Compensation Expenses
Number of stock-based awards outstanding at period end (in shares)	124,470
Cost of sales
Stock-based Compensation Expenses
Stock-based compensation expense (benefit) before income tax benefit	$ 392,000	$ 778,000	1,110,000
Selling, general and administrative expenses
Stock-based Compensation Expenses
Stock-based compensation expense (benefit) before income tax benefit	2,479,000	4,777,000	7,960,000
Research and development expenses
Stock-based Compensation Expenses
Stock-based compensation expense (benefit) before income tax benefit	$ 249,000	$ 541,000	$ 1,037,000