v2.4.0.8
Document and Entity Information
3 Months Ended
Sep. 30, 2014
Nov. 06, 2014
Document and Entity Information    
Entity Registrant Name Xencor Inc  
Entity Central Index Key 0001326732  
Document Type 10-Q  
Document Period End Date Sep. 30, 2014  
Amendment Flag false  
Current Fiscal Year End Date --12-31  
Entity Current Reporting Status Yes  
Entity Filer Category Non-accelerated Filer  
Entity Common Stock, Shares Outstanding   31,395,626
Document Fiscal Year Focus 2014  
Document Fiscal Period Focus Q3