Quarterly report pursuant to Section 13 or 15(d)

Organization and Summary of Significant Accounting Policies - Additional Information (Detail)

v3.19.2
Organization and Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)
$ in Thousands
3 Months Ended 6 Months Ended
Jun. 30, 2019
Jun. 30, 2018
Jun. 30, 2019
Jun. 30, 2018
Jan. 31, 2019
Jan. 01, 2019
Dec. 31, 2018
Organization And Summary Of Significant Accounting Policies [Line Items]              
Reclassification from other current assets to grants revenue receivable $ 5,160   $ 5,160       $ 4,329
Right-of-use asset 10,796   10,796   $ 7,200 $ 4,180 0
Lease liabilities 11,678   11,678   $ 7,200    
Accounts receivable 0   0       $ 240
Takeda Pharmaceuticals Inc              
Organization And Summary Of Significant Accounting Policies [Line Items]              
Accounts receivable $ 0   $ 0        
Revenue | Credit Risk              
Organization And Summary Of Significant Accounting Policies [Line Items]              
Percentage of total revenues 96.00% 68.00% 93.00% 59.00%      
ASU 2016-02              
Organization And Summary Of Significant Accounting Policies [Line Items]              
Right-of-use asset           4,180  
Lease liabilities           $ 4,700