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Account Receivable and Contract Assets (Tables) | 9 Months Ended
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Jan. 31, 2022
Account Receivable And Contract Assets |
Schedule of Accounts Receivable, Contract Assets and Contract Liabilities | The following provides further details on the balance sheet accounts of accounts receivable and contract assets from contracts with customers: Schedule of Accounts Receivable, Contract Assets and Contract Liabilities
|  | January 31, 2022 |  |  | April 30, 2021 |
|  | (in thousands) |
Accounts receivable |  | $ | 113 |  |  | $ | 350 |
Contract assets |  |  | 407 |  |  |  | 190 |
Contract liabilities |  |  | 15 |  |  |  | — |
Schedule of Significant Changes in Contract Assets and Contract Liabilities | Schedule of Significant Changes in Contract Assets and Contract Liabilities
|  | Nine months ended January 31, 2022 |
|  | (in thousands) |
Transferred to receivables from contract assets recognized at the beginning of the period |  | $ | (190 | )
Revenue recognized and not billed as of the end of the period |  |  | 407 |
Net change in contract assets |  | $ | 217 |

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- Definition Schedule Of Accounts Receivable Contract Assets And Contract Liabilities [Table Text Block] + References No definition available. + Details
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- Definition Tabular disclosure of receivable, contract asset, and contract liability from contract with customer. Includes, but is not limited to, change in contract asset and contract liability. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 606 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=123351226&loc=SL49130551-203045 + Details
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