v2.4.0.8
Summary of Significant Accounting Policies - Additional Information (Detail) (USD $)
Share data in Millions, unless otherwise specified
 12 Months Ended
Dec. 28, 2013
segment
Dec. 29, 2012
Dec. 31, 2011
Summary Of Significant Accounting Policies [Line Items]      
Short-term investments $ 0 $ 0  
Cash balance 67,700,000 38,000,000  
Cash equivalents 27,800,000 33,600,000  
U.S. Treasury bills 26,000,000 32,000,000  
Money market funds 1,800,000 1,600,000  
Accounts receivable, net of allowance for doubtful accounts 76,759,000 67,911,000  
Number of days after which royalty report and payment is received 60 days    
Royalties receivable 7,300,000 7,130,000  
Accumulated depreciation and amortization on property and equipment 8,300,000 7,300,000 5,800,000
Accumulated amortization 9,814,000 6,915,000  
Cost of patents, Gross 6,700,000 5,400,000  
Cost of trademarks, Gross 700,000 600,000  
Product life estimate 7 years    
Amount amortized by company 200,000 200,000 200,000
Unamortized cost by company 300,000 500,000  
Impairment of goodwill, intangible assets and other long-lived assets 0 0 0
Number of Sources of Product Revenue 4    
Rate of royalty agreed to be paid 7.75%    
Number of days royalty revenue is adjusted subsequent to quarter end 60 days    
Advertising costs 9,500,000 9,500,000 5,600,000
Foreign currency transaction gain (loss) 4,000,000 1,600,000 100,000
Options to purchase of shares of common stock 7.2 6.4 4.5
Number of reportable segments 1    
Patents
      
Summary Of Significant Accounting Policies [Line Items]      
Estimated life maximum 10 years    
Accumulated amortization 5,679,000 4,591,000  
Total renewal costs capitalized 500,000    
Weighted average number of years until the next renewal 1 year    
Trademarks
      
Summary Of Significant Accounting Policies [Line Items]      
Estimated life maximum 17 years    
Accumulated amortization 653,000 464,000  
Total renewal costs capitalized 400,000    
Weighted average number of years until the next renewal 6 years    
Patents and trademarks
      
Summary Of Significant Accounting Policies [Line Items]      
Accumulated amortization $ 2,700,000 $ 2,100,000 $ 1,600,000
Minimum
      
Summary Of Significant Accounting Policies [Line Items]      
Property and equipment, useful life 3 years    
Product life estimate 3 years    
Warranty period for defects in material and workmanship 6 months    
Maximum
      
Summary Of Significant Accounting Policies [Line Items]      
Property and equipment, useful life 5 years    
Product life estimate 7 years    
Warranty period for defects in material and workmanship 1 year