Quarterly report pursuant to Section 13 or 15(d)

Document and Entity Information

v3.20.1
Document and Entity Information - shares
3 Months Ended
Mar. 31, 2020
May 01, 2020
Document And Entity Information [Abstract]    
Document Type 10-Q  
Document Period End Date Mar. 31, 2020  
Entity Registrant Name XOMA Corp  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Accelerated Filer  
Entity Small Business true  
Entity Emerging Growth Company false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   11,014,673
Entity Central Index Key 0000791908  
Current Fiscal Year End Date --12-31  
Document Fiscal Year Focus 2020  
Document Fiscal Period Focus Q1  
Amendment Flag false