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Stockholders' Equity and Stock-Based Compensation - Employee Stock Purchase Plan Assumptions (Details) - Employee Stock Purchase Plan [Member]
12 Months Ended
Dec. 30, 2017
Dec. 31, 2016
Dec. 26, 2015
Assumption of stock option's fair value      
Expected life 6 months 6 months 6 months
Volatility 37.20% 38.70% 36.90%
Risk free interest rate 0.91% 0.44% 0.12%
Dividends 0.00% 0.00% 0.00%