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Stock-Based Compensation - Schedule of Employee Stock Purchase Plan (Details) - ESPP
3 Months Ended 9 Months Ended
Sep. 30, 2018
Oct. 01, 2017
Sep. 30, 2018
Oct. 01, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Expected term (months) 6 months 6 months 6 months 6 months
Risk-free interest rate 2.09% 1.02% 2.09% 1.02%
Volatility 44.76% 49.71% 44.76% 49.71%
Dividend yield 0.00% 0.00% 0.00% 0.00%