v3.10.0.1
Document and Entity Information - shares
9 Months Ended
Sep. 30, 2018
Nov. 05, 2018
Document Information [Line Items]    
Entity Registrant Name Enstar Group LTD  
Entity Central Index Key 0001363829  
Trading Symbol ESGR  
Current Fiscal Year End Date --12-31  
Entity Filer Category Large Accelerated Filer  
Entity Emerging Growth Company false  
Entity Small Business false  
Document Type 10-Q  
Document Period End Date Sep. 30, 2018  
Document Fiscal Year Focus 2018  
Document Fiscal Period Focus Q3  
Amendment Flag false  
Voting Ordinary Shares    
Document Information [Line Items]    
Entity Common Stock, Shares Outstanding   17,951,076
Non-Voting Convertible Ordinary Shares    
Document Information [Line Items]    
Entity Common Stock, Shares Outstanding   3,509,682