EQUITY AWARD PLANS - RSU (Details) - RSUs - $ / shares
6 Months Ended
Jan. 31, 2017
Jul. 31, 2016
Number of Shares    
Outstanding, beginning balance (in shares) 12,265,369  
Granted (in shares) 8,020,980  
Released (in shares) (4,375)  
Canceled/forfeited (in shares) (410,208)  
Outstanding, ending balance (in shares) 19,871,766  
Grant Date Fair Value per Share    
Outstanding (in dollars per share) $ 16.74 $ 13.23
Granted (in dollars per share) 21.98  
Released (in dollars per share) 14.80  
Canceled/forfeited (in dollars per share) $ 14.82