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Stockholders' Equity and Stock-Based Compensation - Stock Options and Employee Stock Purchase Plan Valuation Assumptions (Details)
3 Months Ended 6 Months Ended
Jun. 27, 2015
Jun. 28, 2014
Jun. 27, 2015
Jun. 28, 2014
Stock Options [Member]        
Assumption of stock option's fair value        
Expected life   4 years 7 months 6 days   4 years 7 months 6 days
Volatility   52.00%   54.90%
Risk free interest rate   1.56%   1.54%
Dividends   0.00%   0.00%
Employee Stock Purchase Plan [Member]        
Assumption of stock option's fair value        
Expected life 6 months 6 months 6 months 6 months
Volatility 37.20% 32.60% 37.20% 32.60%
Risk free interest rate 0.11% 1.00% 0.11% 1.00%
Dividends 0.00% 0.00% 0.00% 0.00%