Document And Entity Information
9 Months Ended
Sep. 30, 2015
Nov. 04, 2015
Document and Entity Information [Abstract]    
Entity Registrant Name Celsion CORP  
Trading Symbol clsn  
Document Type 10-Q  
Current Fiscal Year End Date --12-31  
Entity Common Stock, Shares Outstanding   23,237,617
Amendment Flag false  
Entity Central Index Key 0000749647  
Entity Current Reporting Status Yes  
Entity Voluntary Filers No  
Entity Filer Category Accelerated Filer  
Entity Well-known Seasoned Issuer No  
Document Period End Date Sep. 30, 2015  
Document Fiscal Year Focus 2015  
Document Fiscal Period Focus Q3