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Stock-Based Compensation - Weighted Average Assumptions (Details) - Employee stock purchase plan
3 Months Ended 9 Months Ended
Sep. 24, 2016
Sep. 26, 2015
Sep. 24, 2016
Sep. 26, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Dividend yield 0.00% 0.00% 0.00% 0.00%
Expected volatility 45.30% 52.20% 45.20% 52.10%
Risk-free interest rate 0.45% 0.14% 0.43% 0.10%
Expected term 9 months 9 months 21 days 8 months 14 days 7 months 27 days