v3.19.1
Document and Entity Information - shares
3 Months Ended
Mar. 31, 2019
Apr. 30, 2019
Document and Entity Information [Abstract]    
Entity Registrant Name UNITED COMMUNITY BANKS INC  
Entity Central Index Key 0000857855  
Trading Symbol ucbi  
Current Fiscal Year End Date --12-31  
Entity Filer Category Large Accelerated Filer  
Entity Common Stock Shares Outstanding   79,039,390
Document Type 10-Q  
Document Period End Date Mar. 31, 2019  
Amendment Flag false  
Document Fiscal Year Focus 2019  
Document Fiscal Period Focus Q1