Amount of embedded derivative liability as on inception date.

No definition available.

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Namespace Prefix:	cydy_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as a liability.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The cash inflow from the issuance of a long-term debt instrument which can be exchanged for a specified amount of another security, typically the entity's common stock, at the option of the issuer or the holder.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 14
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=118932676&loc=d3e3255-108585

+ Details

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Balance Type:	debit
Period Type:	duration

- Details

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- Details

Name:	cydy_DateOfInceptionAxis=cydy_InceptionDateOneMember
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Summary of Fair Value of Convertible Note Redemption Provision Derivative Liability (Detail) - USD ($)	9 Months Ended
	Feb. 29, 2020	Feb. 28, 2019	May 31, 2019
Net Proceeds	$ 0	$ 15,460,000
Convertible Note Redemption Provision Derivative Liability [Member]
Derivative Liability			$ 2,005,137
Convertible Note Redemption Provision Derivative Liability [Member] \| Inception date June 2018 Note, November 15, 2018 [Member]
Net Proceeds	5,000,000
Inception Date	1,284,988
Derivative Liability			847,103
Convertible Note Redemption Provision Derivative Liability [Member] \| Inception date January 2019 Note, January 30, 2019 [Member]
Net Proceeds	5,000,000
Inception Date	$ 1,465,008
Derivative Liability			$ 1,158,034