Quarterly report pursuant to Section 13 or 15(d)

Basis of Presentation and Summary of Significant Accounting Policies - Accounting for Share-Based Compensation (Details)

v3.19.2
Basis of Presentation and Summary of Significant Accounting Policies - Accounting for Share-Based Compensation (Details) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Basis of Presentation [Line Items]        
Share-based compensation expense $ 6,571 $ 4,812 $ 11,918 $ 9,367
Research and development expenses        
Basis of Presentation [Line Items]        
Share-based compensation expense 2,528 2,096 4,655 3,863
General and administrative expenses        
Basis of Presentation [Line Items]        
Share-based compensation expense $ 4,043 $ 2,716 $ 7,263 $ 5,504