Document and Entity Information - shares
9 Months Ended
Sep. 30, 2017
Nov. 15, 2017
Document And Entity Information [Abstract]    
Trading Symbol EBIO  
Entity Registrant Name Eleven Biotherapeutics, Inc.  
Entity Central Index Key 0001485003  
Current Fiscal Year End Date --12-31  
Entity Filer Category Smaller Reporting Company  
Document Type 10-Q  
Document Period End Date Sep. 30, 2017  
Document Fiscal Year Focus 2017  
Document Fiscal Period Focus Q3  
Amendment Flag false  
Entity Common Stock, Shares Outstanding   31,831,995