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Stock-Based Compensation - Schedule of Employee Stock Purchase Plan (Details) - ESPP
3 Months Ended 6 Months Ended
Jun. 30, 2019
Jul. 01, 2018
Jun. 30, 2019
Jul. 01, 2018
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 2.40% 2.09% 2.40% 2.09%
Volatility 53.77% 44.76% 53.77% 44.76%
Dividend yield 0.00% 0.00% 0.00% 0.00%