Number of additional shares that can be issued upon shareholder approval.

No definition available.

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- Definition

Payment of sales commission.

+ References

No definition available.

+ Details

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- Definition

Percentage of outstanding common stock limit for shareholder approval.

+ References

No definition available.

+ Details

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- Definition

The cash inflow associated with the amount received from entity's first offering of stock to the public.

+ References

No definition available.

+ Details

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- Definition

Number of shares can be issued based upon outstanding percentage.

+ References

No definition available.

+ Details

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- Definition

Aggregate purchase of common stock.

+ References

No definition available.

+ Details

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- Definition

Amount of consideration received by subsidiary or equity investee in exchange for shares of stock issued or sold. Includes amount of cash received, fair value of noncash assets received, and fair value of liabilities assumed by the investor.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

- Details

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- Details

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Common Stock (Details Narrative) - USD ($) $ / shares in Units, $ in Thousands						9 Months Ended	12 Months Ended
	Dec. 23, 2020	Nov. 20, 2020	Sep. 18, 2020	Oct. 24, 2019	Jan. 07, 2019	Jan. 31, 2021	Apr. 30, 2021
2019 ATM Facility [Member] \| Alliance Global Partners [Member]
Aggregate offering price					$ 25,000
Number of common stock shares sold					17,595,472
Proceeds from issuance or sale of equity, net of issuance costs					$ 23,400
Combined purchase price per share					$ 1.33
Payment of sales commission					$ 800
2019 ATM Facility [Member] \| Alliance Global Partners [Member] \| Forecast [Member]
Number of common stock shares sold							12,342,506
Proceeds from issuance or sale of equity, net of issuance costs							$ 18,700
Combined purchase price per share							$ 1.51
Payment of sales commission							$ 800
2020 ATM Facility [Member] \| Alliance Global Partners [Member]
Aggregate offering price		$ 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
Payment of sales commission						$ 1,600
Stock Purchase Agreement [Member] \| Aspire Capital Fund, LLC [Member]
Number of common stock shares sold			6,424,205			2,250,000
Proceeds from issuance or sale of equity, net of issuance costs			$ 4,000			$ 7,400
Combined purchase price per share			$ 0.63			$ 3.28
Aggregate purchase of common stock			$ 12,500
Percentage of outstanding common stock limit for shareholder approval	19.99%		19.99%
Number of shares can be issued based upon outstanding percentage			3,722,251
Number of additional shares that can be issued upon shareholder approval	9,864,706
Stock Purchase Agreement [Member] \| Aspire Capital Fund, LLC [Member] \| Maximum [Member]
Aggregate purchase of common stock				$ 10,000
Stock Purchase Agreement [Member] \| Aspire Capital Fund, LLC [Member]
Number of common stock shares sold						5,025,000
Proceeds from issuance or sale of equity, net of issuance costs						$ 2,900,000
Combined purchase price per share						$ 0.57