Presentation and Summary of Significant Accounting Policies - Capitalized Computer Software Development Costs (Details) - USD ($) $ in Thousands	Apr. 30, 2022	Apr. 30, 2021
Accounting Policies [Abstract]
Capitalized computer software development costs	$ 43,593	$ 43,593
Accumulated amortization	(42,007)	(38,826)
Capitalized software, net	$ 1,586	$ 4,767

No definition available.

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- Definition

For each balance sheet presented, the amount of accumulated amortization for capitalized computer software costs.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 985
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756

+ Details

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- Definition

Amount before accumulated amortization of capitalized costs for computer software, including but not limited to, acquired and internally developed computer software.

+ References

+ Details

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- Definition

The carrying amount of capitalized computer software costs net of accumulated amortization as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 985
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6501960&loc=d3e128462-111756

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