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Equity Incentive Plans and Stock-Based Compensation - Stock-based Compensation/Stock Repurchase Program (Details) - USD ($)
9 Months Ended
Sep. 30, 2017
Oct. 23, 2017
Oct. 24, 2016
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Total compensation expense related to unvested awards granted, not yet recognized $ 40,400,000    
Total compensation expense related to unvested awards granted, not yet recognized weighted-average period for recognition (in years) 2 years 5 months    
Common Stock      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Amount authorized to be repurchased     $ 20,000,000.0
Number of shares repurchased during period (in shares) 451,259    
Stock repurchased, average price per share (in dollars per share) $ 6.81    
Remaining authorized amount to purchase $ 15,100,000    
Subsequent event | Common Stock      
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]      
Amount authorized to be repurchased   $ 20,000,000.0