Stock-Based Compensation - Schedule of Non-vested Restricted Stock Activity (Details) - Non-vested Restricted Stock [Member]	6 Months Ended
Oct. 31, 2020 $ / shares shares
Number of Shares, Issued and unvested, Beginning \| shares	13,513
Number of Shares, Granted \| shares
Number of Shares, Vested \| shares
Number of Shares, Cancelled/forfeited \| shares
Number of Shares, Issued and Unvested, Ending \| shares	13,513
Weighted Average Price per Share, Issued and Unvested, Beginning \| $ / shares	$ 1.48
Weighted Average Price per Share, Granted \| $ / shares
Weighted Average Price per Share, Vested \| $ / shares
Weighted Average Price per Share, Cancelled/forfeited \| $ / shares
Weighted Average Price per Share, Issued and Unvested, Ending \| $ / shares	$ 1.48

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(3)
-URI http://asc.fasb.org/extlink&oid=120381028&loc=d3e5070-113901

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 718
-SubTopic 10
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-Paragraph 2
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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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-Paragraph 2
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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

+ References

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-Publisher FASB
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-Topic 718
-SubTopic 10
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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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Stock-Based Compensation - Schedule of Non-vested Restricted Stock Activity (Details) - Non-vested Restricted Stock [Member]	6 Months Ended
	Oct. 31, 2020 $ / shares shares
Number of Shares, Issued and unvested, Beginning \| shares	13,513
Number of Shares, Granted \| shares
Number of Shares, Vested \| shares
Number of Shares, Cancelled/forfeited \| shares
Number of Shares, Issued and Unvested, Ending \| shares	13,513
Weighted Average Price per Share, Issued and Unvested, Beginning \| $ / shares	$ 1.48
Weighted Average Price per Share, Granted \| $ / shares
Weighted Average Price per Share, Vested \| $ / shares
Weighted Average Price per Share, Cancelled/forfeited \| $ / shares
Weighted Average Price per Share, Issued and Unvested, Ending \| $ / shares	$ 1.48