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STOCK-BASED COMPENSATION - Summary of Valuation Assumptions (Details) - Stock options
3 Months Ended 9 Months Ended
Sep. 28, 2014
Sep. 27, 2015
Sep. 28, 2014
Black-Scholes Valuation Assumptions      
Expected dividend yield 0.00% 0.00% 0.00%
Expected stock price volatility 65.00% 66.00% 67.00%
Risk-free interest rate 1.40% 1.10% 1.30%
Expected life of options in years 4 years 4 years 4 years