Quarterly report pursuant to Section 13 or 15(d)

Commitments and Contingencies - Additional Information (Detail)

v2.4.1.9
Commitments and Contingencies - Additional Information (Detail) (USD $)
 0 Months Ended 6 Months Ended
Oct. 16, 2012
Nov. 30, 2014
Commitment And Contingencies [Line Items]    
Severance expense   $ 81,000us-gaap_SeveranceCosts1
Severance liabilities   111,000us-gaap_LiabilitiesSubjectToCompromiseEarlyContractTerminationFees
Asset purchase, cash paid 3,500,000us-gaap_PaymentsToAcquireOtherProductiveAssets  
Asset Purchase Agreement Aggregate Consideration Paying Period   10 years
Progenics Pharmaceuticals, Inc.    
Commitment And Contingencies [Line Items]    
Royalty on every net sales   5.00%cydy_PotentialRoyaltyPaymentAsPercentageOfNetSales
/ cydy_BusinessAcquisitionAgreementCounterPartyAxis
= cydy_CompanyAMember
Milestone Payments | US Phase III trial    
Commitment And Contingencies [Line Items]    
Asset purchase, cash paid   1,500,000us-gaap_PaymentsToAcquireOtherProductiveAssets
/ us-gaap_LossContingenciesByNatureOfContingencyAxis
= cydy_MilestonePaymentsMember
/ us-gaap_StatementScenarioAxis
= cydy_ScenarioOneMember
Milestone Payments | US new drug application approval by the FDA    
Commitment And Contingencies [Line Items]    
Asset purchase, cash paid   5,000,000us-gaap_PaymentsToAcquireOtherProductiveAssets
/ us-gaap_LossContingenciesByNatureOfContingencyAxis
= cydy_MilestonePaymentsMember
/ us-gaap_StatementScenarioAxis
= cydy_ScenarioTwoMember
Development Milestone Payments    
Commitment And Contingencies [Line Items]    
Royalty on every net sales   7.50%cydy_PotentialRoyaltyPaymentAsPercentageOfNetSales
/ us-gaap_LossContingenciesByNatureOfContingencyAxis
= cydy_DevelopmentMilestonePaymentsMember
Asset Purchase Agreement Aggregate Consideration Paying Period   10 years
Minimum annual license maintenance fees   150,000cydy_LicenseFeePayments
/ us-gaap_LossContingenciesByNatureOfContingencyAxis
= cydy_DevelopmentMilestonePaymentsMember
Development Milestone Payments | US Phase III trial    
Commitment And Contingencies [Line Items]    
Asset purchase, cash paid   1,000,000us-gaap_PaymentsToAcquireOtherProductiveAssets
/ us-gaap_LossContingenciesByNatureOfContingencyAxis
= cydy_DevelopmentMilestonePaymentsMember
/ us-gaap_StatementScenarioAxis
= cydy_ScenarioOneMember
Development Milestone Payments | US new drug application approval by the FDA    
Commitment And Contingencies [Line Items]    
Asset purchase, cash paid   500,000us-gaap_PaymentsToAcquireOtherProductiveAssets
/ us-gaap_LossContingenciesByNatureOfContingencyAxis
= cydy_DevelopmentMilestonePaymentsMember
/ us-gaap_StatementScenarioAxis
= cydy_ScenarioTwoMember
Development Milestone Payments | New Drug Application with the FDA    
Commitment And Contingencies [Line Items]    
Asset purchase, cash paid   500,000us-gaap_PaymentsToAcquireOtherProductiveAssets
/ us-gaap_LossContingenciesByNatureOfContingencyAxis
= cydy_DevelopmentMilestonePaymentsMember
/ us-gaap_StatementScenarioAxis
= cydy_ScenarioThreeMember
Director    
Commitment And Contingencies [Line Items]    
Salary   13,890us-gaap_SalariesWagesAndOfficersCompensation
/ us-gaap_TitleOfIndividualAxis
= us-gaap_DirectorMember
Cash severance payment   $ 13,890cydy_MonthlySeverancePay
/ us-gaap_TitleOfIndividualAxis
= us-gaap_DirectorMember
Severance period   33 months
Reimbursement of health insurance period   9 months
Director | Stock Option Award Agreement dated Dec 6,2010    
Commitment And Contingencies [Line Items]    
Stock option award agreement   500,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableNumber
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= cydy_StockOptionAwardAgreementDatedDecemberSixTwoThousandAndTenMember
/ us-gaap_TitleOfIndividualAxis
= us-gaap_DirectorMember
Stock Option granted, per share   $ 1.19us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= cydy_StockOptionAwardAgreementDatedDecemberSixTwoThousandAndTenMember
/ us-gaap_TitleOfIndividualAxis
= us-gaap_DirectorMember
Director | Stock Option Award Agreement dated September 22,2010    
Commitment And Contingencies [Line Items]    
Options granted   25,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsGrantsInPeriod
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= cydy_StockOptionAwardAgreementDatedSeptemberTwentyTwoTwoThousandAndTenMemberMember
/ us-gaap_TitleOfIndividualAxis
= us-gaap_DirectorMember
Director | Stock Option Award Agreement dated April 16,2012    
Commitment And Contingencies [Line Items]    
Stock option award agreement   750,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableNumber
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= cydy_StockOptionAwardAgreementDatedAprilSixteenTwoThousandAndTwelveMember
/ us-gaap_TitleOfIndividualAxis
= us-gaap_DirectorMember
Stock Option granted, per share   $ 2.00us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsVestedAndExpectedToVestExercisableWeightedAverageExercisePrice
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= cydy_StockOptionAwardAgreementDatedAprilSixteenTwoThousandAndTwelveMember
/ us-gaap_TitleOfIndividualAxis
= us-gaap_DirectorMember
Option immediate vesting   1,500,000us-gaap_StockIssuedDuringPeriodSharesStockOptionsExercised
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= cydy_StockOptionAwardAgreementDatedAprilSixteenTwoThousandAndTwelveMember
/ us-gaap_TitleOfIndividualAxis
= us-gaap_DirectorMember
Options forfeiture   750,000us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardOptionsForfeituresInPeriod
/ us-gaap_MajorTypesOfDebtAndEquitySecuritiesAxis
= cydy_StockOptionAwardAgreementDatedAprilSixteenTwoThousandAndTwelveMember
/ us-gaap_TitleOfIndividualAxis
= us-gaap_DirectorMember