Quarterly report pursuant to Section 13 or 15(d)

Research and Development Agreements - Schedule of Research and Development Revenue from Related Party Relates to Revenue from Research and Development Agreements (Detail)

v3.20.1
Research and Development Agreements - Schedule of Research and Development Revenue from Related Party Relates to Revenue from Research and Development Agreements (Detail) - USD ($)
$ in Thousands
3 Months Ended
Mar. 31, 2020
Mar. 31, 2019
Revenue Recognition [Line Items]    
Total research and development revenue $ 1,800 $ 6,413
Millennium Pharmaceuticals Inc    
Revenue Recognition [Line Items]    
Total research and development revenue 333 6,413
Millennium Pharmaceuticals Inc | Takeda Individual Project Agreement    
Revenue Recognition [Line Items]    
Total research and development revenue 0 54
Millennium Pharmaceuticals Inc | Takeda Development Agreement    
Revenue Recognition [Line Items]    
Total research and development revenue 147 6,114
Millennium Pharmaceuticals Inc | Takeda Multi Target Agreement    
Revenue Recognition [Line Items]    
Total research and development revenue $ 186 $ 245