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Stock-Based Compensation - Schedule of Weighted Average Assumptions (Details) - ESPP
3 Months Ended 6 Months Ended
Jun. 28, 2020
Jun. 30, 2019
Jun. 28, 2020
Jun. 30, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Expected term (months) 6 months 2 days 6 months 6 months 2 days 6 months
Risk-free interest rate 0.15% 2.40% 0.15% 2.40%
Volatility 88.35% 53.77% 88.35% 53.77%
Dividend yield 0.00% 0.00% 0.00% 0.00%