Provision for Income Taxes - Components of Deferred Tax Assets and Liabilities (Details) - USD ($) $ in Thousands	Apr. 30, 2022	Apr. 30, 2021
Income Tax Disclosure [Abstract]
Accrued liabilities	$ 162	$ 232
Right of use, net asset/liability	316	271
Depreciation and amortization	(396)	(206)
Stock-based compensation expense	3,874	3,640
Net operating loss carry-forward	11,546	11,404
Total deferred tax assets	15,502	15,341
Less: Valuation allowance	(15,502)	(15,341)
Net deferred tax asset	$ 0	$ 0

Deferred Tax Assets, Tax Deferred Expense, Right Of Use Asset (Liability)

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Amount before allocation of valuation allowances of deferred tax liability attributable to deductible temporary differences from depreciation and amortization.

+ References

No definition available.

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 2
-URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319

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

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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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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- Definition

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

+ References

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