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Schedule of Significant Changes in Contract Liabilities (Details) - USD ($) $ in Thousands | 12 Months Ended
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Apr. 30, 2023 | Apr. 30, 2022
Account Receivable Contract Assets And Contract Liabilities |  |
Revenue recognized that was included in the contract liabilities balance as of the beginning of the period | $ (574) |
Contract liabilities obtained in acquisition of MAR |  | (203)
Payments collected for which revenue has not been recognized | 1,823 | 129
Net change in contract liabilities | $ 1,249 | $ (74)

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- Definition Amount of 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 606 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479837/606-10-45-1 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Topic 606 -SubTopic 10 -Name Accounting Standards Codification -Section 50 -Paragraph 8 -Subparagraph (a) -Publisher FASB -URI https://asc.fasb.org//1943274/2147479806/606-10-50-8 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 606 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147479837/606-10-45-2 + Details
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