Acquisitions (Identifiable Intangible Assets) (Details) - USD ($)
$ in Thousands
9 Months Ended
Jan. 29, 2016
Sep. 30, 2016
Dec. 31, 2015
Identifiable Intangible Assets      
Weighted average amortization period   6 years 9 months 18 days  
Goodwill      
Goodwill   $ 17,016 $ 2,760
Customer relationships      
Identifiable Intangible Assets      
Weighted average amortization period   7 years 10 months 24 days  
Trademark/trade name      
Identifiable Intangible Assets      
Weighted average amortization period   12 years  
Developed technology      
Identifiable Intangible Assets      
Weighted average amortization period   4 years 10 months 24 days  
Non-competition agreements      
Identifiable Intangible Assets      
Weighted average amortization period   2 years  
Pakedge Device And Software Inc.      
Goodwill      
Goodwill $ 13,876    
Other      
Revenue associated with acquisition   $ 16,100  
Net income associated with acquisition   2,300  
Pakedge Device And Software Inc. | Minimum      
Identifiable Intangible Assets      
Discount rate used 15.00%    
Pakedge Device And Software Inc. | Maximum      
Identifiable Intangible Assets      
Discount rate used 17.00%    
Pakedge Device And Software Inc. | Customer relationships      
Identifiable Intangible Assets      
Acquired intangible assets $ 8,800    
Weighted average amortization period 8 years    
Pakedge Device And Software Inc. | Trademark/trade name      
Identifiable Intangible Assets      
Acquired intangible assets $ 4,400    
Weighted average amortization period 12 years    
Pakedge Device And Software Inc. | Developed technology      
Identifiable Intangible Assets      
Acquired intangible assets $ 9,700    
Weighted average amortization period 5 years    
Pakedge Device And Software Inc. | Non-competition agreements      
Identifiable Intangible Assets      
Acquired intangible assets $ 300    
Weighted average amortization period 2 years    
Pakedge Device And Software Inc. | Cost of revenue and general and administrative expense      
Other      
Acquisition related costs   3,200  
Pakedge Device And Software Inc. | Cost of revenue      
Other      
Cost of step-up in inventory   $ 2,000