Annual report pursuant to Section 13 and 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
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Revenue Recognition [Line Items]    
Total research and development revenue - from related party $ 19,499 $ 7,283
Takeda Pharmaceuticals Inc    
Revenue Recognition [Line Items]    
Total research and development revenue - from related party 19,499 7,087
Takeda Pharmaceuticals Inc | Takeda Collaboration Agreement    
Revenue Recognition [Line Items]    
Total research and development revenue - from related party 0 92
Takeda Pharmaceuticals Inc | Takeda Individual Project Agreement    
Revenue Recognition [Line Items]    
Total research and development revenue - from related party 48 2,191
Takeda Pharmaceuticals Inc | Takeda Development Agreement    
Revenue Recognition [Line Items]    
Total research and development revenue - from related party 18,468 3,903
Takeda Pharmaceuticals Inc | Takeda Multi Target Agreement    
Revenue Recognition [Line Items]    
Total research and development revenue - from related party $ 983 $ 901