Quarterly report pursuant to Section 13 or 15(d)

Stock-Based Compensation - Stock-Based Compensation Expense (Detail)

v3.7.0.1
Stock-Based Compensation - Stock-Based Compensation Expense (Detail) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2017
Jun. 30, 2016
Jun. 30, 2017
Jun. 30, 2016
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]        
Total stock-based compensation expense $ 1,964 $ 7,199 $ 4,751 $ 10,393
Research and development [Member]        
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]        
Total stock-based compensation expense 1,218 1,728 2,436 3,578
General and administrative [Member]        
Employee Service Share Based Compensation Allocation Of Recognized Period Costs [Line Items]        
Total stock-based compensation expense $ 746 $ 5,471 $ 2,315 $ 6,815