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STOCK-BASED COMPENSATION - Schedule of Weighted Average Assumptions (Details) - ESPP
12 Months Ended
Dec. 30, 2018
Dec. 31, 2017
Jan. 01, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Expected life (months) 6 years 6 years 1 month 6 days 6 years 1 month 6 days
Risk-free interest rate 2.26% 1.22% 0.97%
Volatility 50.00% 53.00% 59.00%
Dividend yield 0.00% 0.00% 0.00%