Quarterly report pursuant to Section 13 or 15(d)

Stock Plans - Additional Information (Detail)

v3.10.0.1
Stock Plans - Additional Information (Detail) - USD ($)
$ / shares in Units, $ in Thousands
 1 Months Ended 6 Months Ended
Jun. 29, 2018
Jan. 31, 2018
Jun. 30, 2018
Jun. 30, 2017
Dec. 31, 2017
Class of Stock [Line Items]          
Accrued employee contributions     $ 2,010   $ 3,117
2014 Plan Stock Options/Stock Issuance Plan and 2017 Stock Incentive Plan [Member]          
Class of Stock [Line Items]          
Options exercise price     $ 20.39    
Unrecognized compensation expense related to stock options     $ 53,272    
Employee Stock Purchase Plan [Member]          
Class of Stock [Line Items]          
Common stock granted   35,812      
Accrued employee contributions     $ 498    
2018 Performance- Based Stock Incentive Plan [Member]          
Class of Stock [Line Items]          
Number of shares authorized for issuance     4,200,000    
Total grant date fair value of stock options vested $ 30,375        
2018 Performance- Based Stock Incentive Plan [Member] | Chad Steelberg and Ryan Steelberg [Member]          
Class of Stock [Line Items]          
Options exercise Period     30 days    
Options exercise price     $ 21.25    
Restricted Stock [Member] | 2014 Plan Stock Options/Stock Issuance Plan and 2017 Stock Incentive Plan [Member]          
Class of Stock [Line Items]          
Unrecognized cost of share-based compensation awards     $ 671    
Cost of share-based compensation awards, recognition period     1 year 10 months 24 days    
Restricted Stock Units [Member] | 2014 Plan Stock Options/Stock Issuance Plan and 2017 Stock Incentive Plan [Member]          
Class of Stock [Line Items]          
Unrecognized cost of share-based compensation awards     $ 569    
Cost of share-based compensation awards, recognition period     1 year    
Stock Options [Member]          
Class of Stock [Line Items]          
Total grant date fair value of stock options vested     $ 4,626 $ 572  
Weighted Average Grant Date Fair Value, Granted     $ 9.73 $ 8.91  
Aggregate intrinsic value of the options exercised     $ 1,698 $ 15  
Stock Options [Member] | 2014 Plan Stock Options/Stock Issuance Plan and 2017 Stock Incentive Plan [Member]          
Class of Stock [Line Items]          
Cost of share-based compensation awards, recognition period     3 years 3 months 18 days    
Performance-based Stock Options [Member] | 2018 Performance- Based Stock Incentive Plan [Member] | Chad Steelberg [Member]          
Class of Stock [Line Items]          
Common stock granted     1,809,900    
Performance-based Stock Options [Member] | 2018 Performance- Based Stock Incentive Plan [Member] | Ryan Steelberg [Member]          
Class of Stock [Line Items]          
Common stock granted     1,357,425