v3.10.0.1
Net Income (Loss) per Share Attributable to Common Stockholders - Antidilutive Securities (Details) - shares
shares in Thousands
3 Months Ended 9 Months Ended
Sep. 29, 2018
Sep. 30, 2017
Sep. 29, 2018
Sep. 30, 2017
Stock options        
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Antidilutive securities (shares) 568 1,385 843 1,334
Restricted stock units        
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Antidilutive securities (shares) 1,048 184 808 108
Series A Redeemable Convertible Preferred Stock (as converted to common stock)        
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]        
Antidilutive securities (shares) 4,983 5 4,983 5