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Stockholders' Equity and Stock-Based Compensation - Employee Stock Purchase Plan Assumptions (Details) - Employee Stock Purchase Plan [Member]
3 Months Ended 9 Months Ended
Sep. 30, 2017
Sep. 24, 2016
Sep. 30, 2017
Sep. 24, 2016
Assumption of stock option's fair value        
Expected life 6 months 6 months 6 months 6 months
Volatility 38.90% 38.20% 37.20% 38.70%
Risk free interest rate 1.13% 0.37% 0.91% 0.44%
Dividends 0.00% 0.00% 0.00% 0.00%