Quarterly report pursuant to Section 13 or 15(d)

Subsequent Event (Details)

v3.20.1
Subsequent Event (Details)
Apr. 15, 2020
Feb. 29, 2020
Dec. 31, 2019
BVF | Xoma Corporation | Common Stock      
Subsequent Event      
Ownership percentage on outstanding shares     27.10%
BVF | Series Y Preferred Stock      
Subsequent Event      
Beneficial ownership limitation (as a percent)   50.00%  
Subsequent Event | BVF | Xoma Corporation | Common Stock      
Subsequent Event      
Ownership percentage on outstanding shares 36.60%