Significant Components of Deferred Income Taxes (Details) - USD ($) $ in Thousands	Jul. 31, 2023	Jul. 31, 2022	Jul. 31, 2021	Jul. 31, 2020
Income Tax Disclosure [Abstract]
Bad debt reserve	$ 1,117	$ 959
Accrued expenses	4,825	3,570
Stock options and restricted stock	361	42
Charitable contributions	724	730
Depreciation	(585)	(640)
Unrealized gain	4,407	2,895
Net operating loss	23,870	40,733
Total deferred income tax assets	34,719	48,289
Valuation allowance	(10,618)	(11,588)	$ (11,540)	$ (58,700)
NET DEFERRED INCOME TAX ASSETS	$ 24,101	$ 36,701

Deferred tax liabilities unrealized loss gains on trading securities

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible charitable contribution carryforwards.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-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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-Topic 740
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-Section 50
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-8

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

+ References

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

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Amount, after allocation of valuation allowances and deferred tax liability, of deferred tax asset attributable to deductible differences and carryforwards, without jurisdictional netting.

+ References

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.

+ References

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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 before allocation of valuation allowances of deferred tax asset attributable to deductible temporary differences from accrued liabilities.

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Amount, before allocation of valuation allowance, of deferred tax asset attributable to deductible temporary difference from allowance for credit loss on accounts receivable.

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- Definition

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

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (c)
-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 property, plant, and equipment.

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