Annual report pursuant to Section 13 and 15(d)

Document and Entity Information

Document and Entity Information (USD $)
12 Months Ended
Jun. 30, 2014
Sep. 08, 2014
Dec. 31, 2013
Document And Entity Information [Abstract]      
Document Type 10-K    
Document Period End Date Jun. 30, 2014    
Amendment Flag false    
Document Fiscal Period Focus FY    
Document Fiscal Year Focus 2014    
Current Fiscal Year End Date --06-30    
Entity Central Index Key 0000061398    
Entity Current Reporting Status Yes    
Entity Filer Category Smaller Reporting Company    
Entity Registrant Name MAGELLAN PETROLEUM CORP /DE/    
Entity Voluntary Filers No    
Entity Well-known Seasoned Issuer No    
Entity Common Stock Shares Outstanding   45,586,778  
Entity Public Float     $ 42,236,074