Earnings (Loss) Per Share - Additional Information (Details) - shares
Apr. 29, 2018
Apr. 30, 2017
Restricted Stock Units    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Restricted shares outstanding 300,928 220,046
Common Stock    
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]    
Options to purchase common stock outstanding 2,360,174 1,871,346