Income Taxes - Tax Effects of Temporary Differences (Details) - USD ($)	Jul. 31, 2026	Jul. 31, 2025
Deferred tax assets:
Inventory and contract reserves	$ 339,000	$ 347,000
Compensation and commissions	3,420,000	3,408,000
Federal, state and foreign research and experimentation credits	8,770,000	7,598,000
Capitalized U.S. research and experimental expenditures	2,240,000	7,029,000
Stock-based compensation	1,735,000	1,656,000
Foreign scientific research and experimental development expenditures	2,014,000	2,006,000
Federal, state and foreign net operating losses	6,364,000	5,367,000
Federal and state capital losses	0	14,473,000
Lease liabilities	3,318,000	3,286,000
Deferred revenue, non-current	2,834,000	3,371,000
Interest expense limitation	23,768,000	13,411,000
Other	2,240,000	2,098,000
Less: valuation allowance	(24,134,000)	(29,102,000)
Total deferred tax assets, net	32,908,000	34,948,000
Deferred tax liabilities:
Plant and equipment	(2,350,000)	(2,009,000)
Lease right-of-use assets	(2,707,000)	(2,584,000)
Intangibles	(27,633,000)	(29,106,000)
Total deferred tax liabilities	$ (32,690,000)	$ (33,699,000)

Deferred Tax Assets, Capitalized Research and Experimental Expenditures

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Deferred Tax Assets, Deferred Revenue Non-Current

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Deferred Tax Assets, Foreign Scientific Research and Experimental Development Costs

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Deferred Tax Assets, Interest Expense Limitation

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from inventory and warranty reserves.

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No definition available.

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Deferred Tax Assets, Operating Lease Liabilities

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from compensation and commissions accruals.

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Amount of deferred tax liability attributable to taxable temporary differences.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-2

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible capital loss carryforwards.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-6

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Amount after allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences and carryforwards.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-2

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary differences, classified as other.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible research tax credit carryforwards.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from share-based compensation.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
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-Section 50
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-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-2

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Amount of deferred tax liability attributable to taxable temporary differences from intangible assets other than goodwill.

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Amount of deferred tax liability attributable to taxable temporary differences from leasing arrangements.

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Amount of deferred tax liability attributable to taxable temporary differences from property, plant, and equipment.

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