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Account Receivable, Contract Assets, and Contract Liabilities (Tables) | 12 Months Ended
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Apr. 30, 2020
Account Receivable Contract Assets And Contract Liabilities |
Schedule of Accounts Receivable | Accounts receivable consisted of the following at April 30, 2020 and 2019.
|  | April 30, 2020 |  |  | April 30, 2019 |
|  | (in thousands) |
Opening balance |  | $ | 63 |  |  | $ | 171 |
Amount invoiced to customers |  |  | 1,386 |  |  |  | 857 |
Collections |  |  | (1,344 | ) |  |  | (965 | )
Ending balance |  | $ | 105 |  |  | $ | 63 |

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- Definition Tabular disclosure of the various types of trade accounts and notes receivable and for each the gross carrying value, allowance, and net carrying value as of the balance sheet date. Presentation is categorized by current, noncurrent and unclassified receivables. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.3,4) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 + Details
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