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v3.21.2

Background, Basis of Presentation and Liquidity (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands |  |  |  |  |  |  | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Dec. 23, 2020 | Nov. 20, 2020 | Sep. 18, 2020 | Oct. 24, 2019 | Apr. 08, 2019 | Jan. 07, 2019 | Jan. 31, 2021 | Jul. 31, 2021 | Jul. 31, 2020 | Apr. 30, 2021
ScheduleBackgroundBasisOfPresentationAndLiquidityLineItems [Line Items] |  |  |  |  |  |  |  |  |  |
Net Income (Loss) Attributable to Parent |  |  |  |  |  |  |  | $ 3,079 | $ 3,385 | $ (14,800)
Net Cash Provided by (Used in) Operating Activities |  |  |  |  |  |  |  | 5,287 | $ 2,737 | $ (11,700)
Cash |  |  |  |  |  |  |  | $ 77,700 |  |
Number of common stock shares sold |  |  |  |  | 1,542,000 |  |  |  |  |
Common Stock, Shares Authorized |  |  |  |  |  |  |  | 100,000,000 |  | 100,000,000
2019 ATM Facility [Member] | A.G.P Alliance Global Partners [Member] |  |  |  |  |  |  |  |  |  |
ScheduleBackgroundBasisOfPresentationAndLiquidityLineItems [Line Items] |  |  |  |  |  |  |  |  |  |
[custom:ProceedsFromInitialPublicOffering] |  |  |  |  |  | $ 25,000 |  |  |  |
Number of common stock shares sold |  |  |  |  |  | 17,595,472 |  |  |  | 12,342,506
Proceeds from issuance or sale of equity, net of issuance costs |  |  |  |  |  | $ 23,400 |  |  |  | $ 18,700
Combined purchase price per share |  |  |  |  |  | $ 1.33 |  |  |  | $ 1.51
[custom:PaymentOfSalesCommission] |  |  |  |  |  |  |  |  |  | $ 800
Two Thousand Twenty ATM Facility [Member] | A.G.P Alliance Global Partners [Member] |  |  |  |  |  |  |  |  |  |
ScheduleBackgroundBasisOfPresentationAndLiquidityLineItems [Line Items] |  |  |  |  |  |  |  |  |  |
[custom:ProceedsFromInitialPublicOffering] |  | $ 50,000 |  |  |  |  |  |  |  |
Number of common stock shares sold |  |  |  |  |  |  |  | 17,179,883 |  |
Proceeds from issuance or sale of equity, net of issuance costs |  |  |  |  |  |  |  | $ 50,000 |  |
Combined purchase price per share |  |  |  |  |  |  |  | $ 2.91 |  |
[custom:PaymentOfSalesCommission] |  |  |  |  |  |  |  | $ 1,600 |  |
Stock Purchase Agreement [Member] | Aspire Capital Fund, LLC [Member] |  |  |  |  |  |  |  |  |  |
ScheduleBackgroundBasisOfPresentationAndLiquidityLineItems [Line Items] |  |  |  |  |  |  |  |  |  |
Number of common stock shares sold |  |  | 6,424,205 |  |  |  | 3,722,251 |  |  |
Proceeds from issuance or sale of equity, net of issuance costs |  |  | $ 4,000 |  |  |  | $ 11,800 | $ 1,000 |  |
Combined purchase price per share |  |  | $ 0.63 |  |  |  | $ 3.17 |  |  |
Aggregate purchase of common stock |  |  | $ 12,500 |  |  |  |  |  |  |
[custom:PercentageOfOutstandingCommonStockLimitForShareholderApproval] | 19.99% |  | 19.99% |  |  |  |  |  |  |
[custom:StockIssuedDuringPeriodSharesCanBeIssuedBasedUponOutstandingPercentage] |  |  | 3,722,251 |  |  |  |  |  |  |
[custom:NumberOfAdditionalSharesThatCanBeIssuedUponShareholderApproval] | 9,864,706 |  |  |  |  |  |  |  |  |
Stock Purchase Agreement [Member] | Aspire Capital Fund, LLC [Member] | Maximum [Member] |  |  |  |  |  |  |  |  |  |
ScheduleBackgroundBasisOfPresentationAndLiquidityLineItems [Line Items] |  |  |  |  |  |  |  |  |  |
Aggregate purchase of common stock |  |  |  | $ 10,000 |  |  |  |  |  |
Stock Purchase Agreement [Member] | Aspire Capital Fund, LLC [Member] |  |  |  |  |  |  |  |  |  |
ScheduleBackgroundBasisOfPresentationAndLiquidityLineItems [Line Items] |  |  |  |  |  |  |  |  |  |
Number of common stock shares sold |  |  |  |  |  |  |  |  |  | 5,025,000
Proceeds from issuance or sale of equity, net of issuance costs |  |  |  |  |  |  |  |  |  | $ 2,900
Combined purchase price per share |  |  |  |  |  |  |  |  |  | $ 0.57

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