Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation - Summary of Stock-Based Compensation Expenses Related to Restricted Stock Units (Detail)

v3.19.3
Stock-Based Compensation - Summary of Stock-Based Compensation Expenses Related to Restricted Stock Units (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 [Line Items]        
Stock-based compensation expense $ 2,705 $ 589 $ 6,565 $ 3,016
Restricted Stock Units [Member]        
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]        
Stock-based compensation expense $ 706 $ 667 $ 2,289 $ 1,890