v3.19.2
Document and Entity Information - shares
6 Months Ended
Jun. 30, 2019
Aug. 13, 2019
Document And Entity Information    
Entity Registrant Name Celsion CORP  
Entity Central Index Key 0000749647  
Document Type 10-Q  
Document Period End Date Jun. 30, 2019  
Amendment Flag false  
Current Fiscal Year End Date --12-31  
Entity Current Reporting Status Yes  
Entity Interactive Data Current Yes  
Entity Filer Category Non-accelerated Filer  
Entity Small Business Flag true  
Entity Emerging Growth Company false  
Entity Ex Transition Period false  
Entity Shell Company false  
Entity Common Stock, Shares Outstanding   21,387,418
Document Fiscal Period Focus Q2  
Document Fiscal Year Focus 2019