Debt Conversion, Converted Instrument, Amount Net

No definition available.

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- Definition

Including the current and noncurrent portions, carrying amount of debt identified as being convertible into another form of financial instrument (typically the entity's common stock) as of the balance sheet date, which originally required full repayment more than twelve months after issuance or greater than the normal operating cycle of the company.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

Reference 2: 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(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(16))
-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

+ Details

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Period Type:	instant

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959

+ Details

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of interest expense incurred on a debt or other obligation to related party.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
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- Details

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- Details

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- Details

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Data Type:	na
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- Details

Name:	us-gaap_DerivativeInstrumentRiskAxis=cydy_CommonStockIssuedMember
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- Details

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Allocation of Cash Proceeds Derivative Liability at Its Fair Value and Warrant at Its Relative Fair Value, with Residual Allocation of Host AVCP Note Agreement (Detail) - USD ($)	12 Months Ended
	May 31, 2018	May 31, 2017	May 31, 2016
Debt Instrument [Line Items]
Beginning Balance			$ 4,862,257
Amortization Debt Discount			94,344
Change in Fair Value	$ (1,690,935)	$ (2,164,533)	(646,505)
Warrants (equity allocation)
Debt Instrument [Line Items]
Beginning Balance			215,732
Loss On Debt Extinguishment
Debt Instrument [Line Items]
Conversion			(584,177)
Compound Embedded Derivative
Debt Instrument [Line Items]
Beginning Balance			2,008,907
Change in Fair Value			(646,505)
Conversion			(1,362,402)
Common Stock Issued
Debt Instrument [Line Items]
Conversion			4,714,168
AVCP Convertible note payable
Debt Instrument [Line Items]
Beginning Balance			2,637,618
Amortization Debt Discount			94,344
Conversion			(2,731,962)
Accrued Unpaid Interest
Debt Instrument [Line Items]
Conversion			$ (35,627)