Segment Information and Significant Customers - Schedule of Total Revenue by Geographic Region (Detail) (USD $)
In Thousands, unless otherwise specified
3 Months Ended 6 Months Ended
Jan. 31, 2015
Jan. 31, 2014
Jan. 31, 2015
Jan. 31, 2014
Revenue, Major Customer [Line Items]        
Revenue $ 212,931 $ 176,356 $ 420,752 $ 337,283
United States [Member]        
Revenue, Major Customer [Line Items]        
Revenue 134,931 113,890 267,696 222,205
Europe, Middle East and Africa [Member]        
Revenue, Major Customer [Line Items]        
Revenue 42,706 33,768 87,563 59,764
Asia Pacific [Member]        
Revenue, Major Customer [Line Items]        
Revenue 29,188 24,260 55,194 47,254
Rest of World [Member]        
Revenue, Major Customer [Line Items]        
Revenue $ 6,106 $ 4,438 $ 10,299 $ 8,060