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Shareholders' Deficit - Assumptions Used to Calculate Fair Value of Options Granted Using Black-Scholes-Merton Option-Pricing Model (Details) - Employee Stock Option
12 Months Ended
Dec. 28, 2019
Dec. 29, 2018
Dec. 30, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected dividend yield 0.00% 0.00% 0.00%
Expected volatility 43.00% 43.00% 46.00%
Risk-free interest rate 2.20% 2.70% 2.00%
Expected term (in years) 5 years 4 months 24 days 5 years 5 years 1 month 6 days