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Stock-Based Compensation (Schedule of Valuation Assumptions) (Details)
3 Months Ended 6 Months Ended
Jun. 30, 2013
Jul. 01, 2012
Apr. 01, 2012
Jun. 30, 2013
Jul. 01, 2012
Stock Options [Member]
         
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Expected term 6 years 5 months 1 day 6 years 6 months 11 days   6 years 1 month 17 days 6 years 2 months 19 days
Risk-free interest rate 1.27% 1.16%   1.18% 1.10%
Expected volatility 59.31% 59.03%   60.44% 59.65%
Expected dividend yield 0.00% 0.00%   0.00% 0.00%
Employee Stock Purchase Plan [Member]
         
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]          
Expected term 6 months 2 days 6 months 2 days   6 months 2 days 6 months 2 days
Risk-free interest rate 0.09% 0.14% 0.14% 0.09%  
Expected volatility 39.03% 67.93% 67.93% 39.03%  
Expected dividend yield 0.00% 0.00% 0.00% 0.00%