Quarterly report pursuant to Section 13 or 15(d)

Stock Plans - Schedule of Stock-based Compensation Expense (Detail)

v3.19.3
Stock Plans - Schedule of Stock-based Compensation Expense (Detail) - USD ($)
$ in Thousands
 3 Months Ended 9 Months Ended
Sep. 30, 2019
Sep. 30, 2018
Sep. 30, 2019
Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]        
Stock-based compensation expense $ 4,764 $ 4,838 $ 16,049 $ 9,963
Sales and Marketing [Member]        
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]        
Stock-based compensation expense 281 246 795 814
Research and Development [Member]        
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]        
Stock-based compensation expense 334 596 2,318 1,103
General and Administrative [Member]        
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]        
Stock-based compensation expense 4,149 3,996 12,936 8,046
Restricted Stock Units [Member]        
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]        
Stock-based compensation expense 251 130 748 277
Restricted Stock Awards [Member]        
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]        
Stock-based compensation expense 47 59 303 412
Machine Box Contingent Common Stock Issuances [Member]        
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]        
Stock-based compensation expense 28   1,255  
Performance-based Stock Options [Member]        
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]        
Stock-based compensation expense 2,000 1,846 5,956 1,900
Stock Options [Member]        
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]        
Stock-based compensation expense 2,329 2,575 7,389 6,857
Employee Stock Purchase Plan [Member]        
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]        
Stock-based compensation expense $ 109 $ 228 $ 398 $ 517