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Schedule of Employee Service Share-based Compensation, Allocation of Recognized Period Costs (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
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Jan. 31, 2022 | Jan. 31, 2021 | Jan. 31, 2022 | Jan. 31, 2021
Total share-based compensation expense | $ 317 | $ 115 | $ 864 | $ 338
Engineering and Product Development [Member] |  |  |  |
Total share-based compensation expense | 209 | 32 | 551 | 91
Selling, General and Administrative Expenses [Member] |  |  |  |
Total share-based compensation expense | $ 108 | $ 83 | $ 313 | $ 247

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- Definition Amount of noncash expense for share-based payment arrangement. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585 + Details
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- Details
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- Details
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