Business Combinations (Schedule of Net Assets Acquired) (Details) - USD ($)
$ in Thousands
 6 Months Ended
Dec. 02, 2014
Oct. 01, 2014
May. 13, 2014
May. 31, 2015
Nov. 30, 2014
Business Acquisition [Line Items]          
Goodwill       $ 370,533 $ 232,836
Telerik AD [Member]          
Business Acquisition [Line Items]          
Net working capital $ 6,612        
Property, plant and equipment 3,108        
Intangible assets 123,100        
Deferred taxes (10,401)        
Deferred revenue (7,915)        
Other non-current liabilities (472)        
Goodwill 137,921        
Net assets acquired $ 251,953        
Acquired intangible assets, useful life 5 years     5 years  
Telerik AD [Member] | Customer Relationships [Member]          
Business Acquisition [Line Items]          
Intangible assets $ 47,100        
BravePoint Inc. [Member]          
Business Acquisition [Line Items]          
Net working capital   $ 2,902      
Property, plant and equipment   735      
Other assets   16      
Deferred revenue   (680)      
Goodwill   2,257      
Net assets acquired   12,000      
BravePoint Inc. [Member] | Customer Relationships [Member]          
Business Acquisition [Line Items]          
Intangible assets   $ 4,110      
Acquired intangible assets, useful life   7 years      
BravePoint Inc. [Member] | Trade Names [Member]          
Business Acquisition [Line Items]          
Intangible assets   $ 850      
Acquired intangible assets, useful life   7 years      
BravePoint Inc. [Member] | Purchased Technology [Member]          
Business Acquisition [Line Items]          
Intangible assets   $ 1,810      
Acquired intangible assets, useful life   3 years      
Modulus [Member]          
Business Acquisition [Line Items]          
Net working capital     $ 7    
Goodwill     6,433    
Net assets acquired     13,950    
Modulus [Member] | Trade Names [Member]          
Business Acquisition [Line Items]          
Intangible assets     $ 190    
Acquired intangible assets, useful life     7 years    
Modulus [Member] | Purchased Technology [Member]          
Business Acquisition [Line Items]          
Intangible assets     $ 7,320    
Acquired intangible assets, useful life     7 years