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Stock-based Compensation (Schedule of Fair Value of Employee Share-Based Payments Awards ESPP Assumptions and Weighted Average Fair Values) (Details)
12 Months Ended
Dec. 28, 2018
Dec. 29, 2017
Dec. 30, 2016
Stock Options [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Risk-free interest rate 2.81% 1.98% 1.15%
Dividend yield 0.00% 0.00% 0.00%
Volatility 55.00% 59.00% 76.00%
Expected life 4 years 4 months 20 days 4 years 5 months 23 days 4 years 4 months 9 days
ESPP [Member]      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Risk-free interest rate 1.93% 1.09% 0.55%
Dividend yield 0.00% 0.00% 0.00%
Volatility 53.00% 58.00% 65.00%
Expected life 6 months 6 months 6 months