Income Taxes (Provision for Income Taxes Differed from Amounts Computed by the U.S. Federal Income Tax Rate) (Details) - USD ($)	12 Months Ended
Jul. 31, 2022	Jul. 31, 2021	Jul. 31, 2020
Amount
Computed "expected" tax expense (benefit)	$ (7,786,000)	$ (15,746,000)	$ 1,955,000
State and local income taxes, net of federal benefit	227,000	(1,371,000)	(278,000)
Stock-based compensation	1,049,000	(20,000)	308,000
Research and experimentation credits	(1,484,000)	(1,018,000)	(1,210,000)
Foreign-derived intangible income deduction	0	164,000	(162,000)
Revaluation of convertible preferred stock option liability	(211,000)	0	0
Nondeductible transaction costs	0	402,000	301,000
Nondeductible executive compensation	2,801,000	628,000	595,000
Fines and penalties	(1,000)	0	189,000
Audit settlements	18,000	6,000	1,000
Change in the beginning of the year valuation allowance for deferred tax assets	0	(805,000)	0
Change in valuation allowance	2,009,000	15,582,000	0
Remeasurement of deferred taxes	(396,000)	(224,000)	(135,000)
Foreign income taxes	(478,000)	676,000	453,000
Other, net	229,000	226,000	273,000
(Benefit from) provision for income taxes	$ (4,023,000)	$ (1,500,000)	$ 2,290,000
Rate
Computed "expected" tax expense (benefit)	21.00%	21.00%	21.00%
State and local income taxes, net of federal benefit	(0.60%)	1.80%	(3.00%)
Stock-based compensation	(2.80%)	0.00%	3.30%
Research and experimentation credits	4.00%	1.40%	(13.00%)
Foreign-derived intangible income deduction	0.00%	(0.20%)	(1.70%)
Revaluation of convertible preferred stock option liability	0.60%	0.00%	0.00%
Nondeductible transaction costs	0.00%	(0.50%)	3.20%
Nondeductible executive compensation	(7.60%)	(0.80%)	6.40%
Fines and penalties	0.00%	0.00%	2.00%
Audit settlements	0.00%	0.00%	0.00%
Change in the beginning of the year valuation allowance for deferred tax assets	0.00%	1.10%	0.00%
Change in valuation allowance	(5.40%)	(20.80%)	0.00%
Remeasurement of deferred taxes	1.10%	0.30%	(1.50%)
Foreign income taxes	1.30%	(0.90%)	4.90%
Other, net	(0.70%)	(0.40%)	3.00%
(Benefit from) provision for income taxes	10.90%	2.00%	24.60%

Effective Income Tax Rate Reconciliation, Change In Valuation Allowance, Amount

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