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Stock Based Compensation - Additional Information (Details) - USD ($)
1 Months Ended 3 Months Ended
Jul. 31, 2017
Oct. 28, 2017
Oct. 29, 2016
Jul. 29, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Stock-based compensation expense   $ 2,038,000 $ 610,000  
Weighted-average grant date fair value of options   $ 7.55 $ 2.53  
Unrecognized compensation expense related to unvested options, net of estimated forfeitures   $ 36,800,000    
Stock Options        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Unrecognized compensation expense related to unvested options weighted average recognition period   3 years 7 months 7 days    
Stock Options | Employees        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Stock-based compensation expense   $ 2,038,000 $ 552,000  
Stock Options | Non-employee        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Stock-based compensation expense   0 $ 58,000  
Stock Options | Certain Members of Executive Management Team        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Stock-based compensation expense   $ 0    
Options granted 1,097,463      
Options vested period 24 months      
Aggregate grant-date fair value of option awards $ 14,000,000      
2011 Equity Incentive Plan        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Number of shares authorized for issuance   23,223,374    
Number of shares available for grant   1,726,679   2,023,424
Options granted   867,865    
2011 Equity Incentive Plan | Stock Options        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Remaining vesting after first anniversary of grant date   3 years    
Options exercisable period   10 years    
2011 Equity Incentive Plan | Stock Options | First Anniversary        
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]        
Employee stock options vesting percentage   25.00%