Quarterly report pursuant to Section 13 or 15(d)

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

v3.20.2
Organization and Summary of Significant Accounting Policies - Additional Information (Detail) - USD ($)
$ in Thousands
3 Months Ended 9 Months Ended
Sep. 30, 2020
Sep. 30, 2019
Sep. 30, 2020
Sep. 30, 2019
Dec. 31, 2019
Organization And Summary Of Significant Accounting Policies [Line Items]          
Reclassification from deferred revenue, current to deferred revenue, current, related party $ 4,566   $ 4,566   $ 8,780
Reclassification from deferred revenue, non-current to deferred revenue, non-current, related party         400
Reclassification from deferred revenue to deferred revenue, related party       $ 12,700  
Cash, cash equivalents, and marketable securities $ 118,200   $ 118,200    
Revenue | Credit Risk | Vertex Pharmaceuticals Inc          
Organization And Summary Of Significant Accounting Policies [Line Items]          
Percentage of total revenues 64.00% 0.00% 47.00% 0.00%  
Revenue | Credit Risk | Takeda          
Organization And Summary Of Significant Accounting Policies [Line Items]          
Percentage of total revenues 36.00% 80.00% 32.00% 90.00%  
Other Assets          
Organization And Summary Of Significant Accounting Policies [Line Items]          
Restricted cash $ 3,700   $ 3,700   $ 3,000