Quarterly report pursuant to Section 13 or 15(d)

Condensed Financial Statements - Summary of Certain Statements of Operations Amounts (Detail)

v3.19.2
Condensed Financial Statements - Summary of Certain Statements of Operations Amounts (Detail) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]        
Stock compensation expense $ 2,304 $ 2,292 $ 3,860 $ 2,224
Research and Development [Member]        
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]        
Stock compensation expense 539 1,325 779 888
Selling and General and Administrative [Member]        
Share-based Compensation Arrangement by Share-based Payment Award, Compensation Cost [Line Items]        
Stock compensation expense $ 1,765 $ 967 $ 3,081 $ 1,336