General form of registration statement for all companies including face-amount certificate companies

Stock Options and Warrants (Detail)

v2.4.1.9
Stock Options and Warrants (Detail) (USD $)
 9 Months Ended 12 Months Ended
Feb. 28, 2015
May 31, 2014
May 31, 2013
May 31, 2012
Stock option and warrant activity        
Options and warrants outstanding, Number of Shares 30,806,361cydy_StockOptionsAndWarrantsOutstandingNumbers 18,146,938cydy_StockOptionsAndWarrantsOutstandingNumbers 10,327,664cydy_StockOptionsAndWarrantsOutstandingNumbers  
Granted, Number of Shares 1,208,973cydy_StockOptionsAndWarrantsGrantsInPeriod 18,414,144cydy_StockOptionsAndWarrantsGrantsInPeriod 11,166,274cydy_StockOptionsAndWarrantsGrantsInPeriod  
Exercised, Number of Shares (1,938,974)cydy_StockOptionsAndWarrantsExercisedInPeriod (50,000)cydy_StockOptionsAndWarrantsExercisedInPeriod (780,000)cydy_StockOptionsAndWarrantsExercisedInPeriod  
Forfeited /expired/ cancelled, Number of Shares (7,020,410)cydy_StockOptionsAndWarrantsForfeituresAndExpirationsInPeriod (5,704,721)cydy_StockOptionsAndWarrantsForfeituresAndExpirationsInPeriod (2,567,000)cydy_StockOptionsAndWarrantsForfeituresAndExpirationsInPeriod  
Options and warrants outstanding, Number of Shares 23,055,950cydy_StockOptionsAndWarrantsOutstandingNumbers 30,806,361cydy_StockOptionsAndWarrantsOutstandingNumbers 18,146,938cydy_StockOptionsAndWarrantsOutstandingNumbers 10,327,664cydy_StockOptionsAndWarrantsOutstandingNumbers
Outstanding exercisable - Number of Shares 21,476,679cydy_StockOptionsAndWarrantsOutstandingExercisableNumber 29,986,581cydy_StockOptionsAndWarrantsOutstandingExercisableNumber    
Options and warrants outstanding, Weighted Average Exercise Price $ 1.13cydy_StockOptionsAndWarrantsOutstandingWeightedAverageExercisePrice $ 1.65cydy_StockOptionsAndWarrantsOutstandingWeightedAverageExercisePrice $ 1.60cydy_StockOptionsAndWarrantsOutstandingWeightedAverageExercisePrice  
Granted, Weighted Average Exercise Price $ 0.67cydy_StockOptionsAndWarrantsGrantsInPeriodWeightedAverageExercisePrice $ 0.74cydy_StockOptionsAndWarrantsGrantsInPeriodWeightedAverageExercisePrice $ 1.61cydy_StockOptionsAndWarrantsGrantsInPeriodWeightedAverageExercisePrice  
Exercised, Weighted Average Exercise Price $ 0.55cydy_StockOptionsAndWarrantsExercisedInPeriodWeightedAverageExercisePrice   $ 0.26cydy_StockOptionsAndWarrantsExercisedInPeriodWeightedAverageExercisePrice  
Forfeited/expired/cancelled, Weighted Average Exercise Price $ 1.76cydy_StockOptionsAndWarrantsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice $ 1.49cydy_StockOptionsAndWarrantsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice $ 1.73cydy_StockOptionsAndWarrantsForfeituresAndExpirationsInPeriodWeightedAverageExercisePrice  
Options and warrants outstanding, Weighted Average Exercise Price $ 0.86cydy_StockOptionsAndWarrantsOutstandingWeightedAverageExercisePrice $ 1.13cydy_StockOptionsAndWarrantsOutstandingWeightedAverageExercisePrice $ 1.65cydy_StockOptionsAndWarrantsOutstandingWeightedAverageExercisePrice $ 1.60cydy_StockOptionsAndWarrantsOutstandingWeightedAverageExercisePrice
Outstanding exercisable, Weighted Average Exercise Price $ 0.86cydy_StockOptionsAndWarrantsOutstandingExercisableWeightedAverageExercisePrice $ 1.15cydy_StockOptionsAndWarrantsOutstandingExercisableWeightedAverageExercisePrice    
Options and warrants outstanding, Weighted Average Remaining Contractual Life 3 years 8 months 23 days 3 years 3 months 15 days 1 year 10 months 10 days 3 years 2 months 12 days
Outstanding exercisable, Weighted Average Remaining Contractual Life 3 years 8 months 19 days 3 years 2 months 16 days    
Options and warrants outstanding , Aggregate Intrinsic Value $ 2,151,361cydy_StockOptionsAndWarrantsOutstandingAggregateIntrinsicValue $ 177,042cydy_StockOptionsAndWarrantsOutstandingAggregateIntrinsicValue $ 140,321cydy_StockOptionsAndWarrantsOutstandingAggregateIntrinsicValue $ 2,308,279cydy_StockOptionsAndWarrantsOutstandingAggregateIntrinsicValue
Exercisable , Aggregate Intrinsic Value $ 2,027,111cydy_StockOptionsAndWarrantsOutstandingExercisableAggregateIntrinsicValue $ 170,042cydy_StockOptionsAndWarrantsOutstandingExercisableAggregateIntrinsicValue