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Schedule of Significant Changes in Contract Liabilities (Details) - USD ($) $ in Thousands | 3 Months Ended
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Jul. 31, 2023 | Jul. 31, 2022
Accounts Receivable Contract Assets And Contract Liabilities |  |
Revenue recognized | $ (321) | $ (91)
Payments collected for which revenue has not been recognized | 150 | 63
Net change in contract liabilities | $ (171) | $ (28)

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- Definition Amount of revenue recognized that was previously included in balance of obligation to transfer good or service to customer for which consideration from customer has been received or is due. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 606 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479806/606-10-50-8 + Details
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- Definition Amount of increase (decrease) in obligation to transfer good or service to customer for which consideration has been received or is receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 912 -SubTopic 310 -Name Accounting Standards Codification -Section 45 -Paragraph 11 -Subparagraph (b) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482312/912-310-45-11 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Topic 230 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 28 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147482740/230-10-45-28 + Details
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