Condensed Financial Statements of United Community Banks, Inc. (Parent Only) - Statements of Income (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Operations
Other	$ 24,142	$ 16,477	$ 16,485
Total income	522,211	440,445	404,281
Interest expense	61,330	33,735	25,236
Other expense	32,514	26,961	24,742
Total expenses	306,285	267,611	241,289
Tax benefit (expense)	(49,815)	(105,013)	(62,336)
Net income	166,111	67,821	100,656
Parent
Statement of Operations
Dividends from bank	161,500	103,200	41,500
Dividends from other subsidiaries	850	0	0
Shared service fees from subsidiaries	10,257	10,481	8,476
Other	133	1,078	685
Total income	172,740	114,759	50,661
Interest expense	11,868	10,258	11,209
Other expense	14,456	14,960	11,380
Total expenses	26,324	25,218	22,589
Tax benefit (expense)	1,640	1,447	6,717
Income before equity in undistributed (loss) earnings of subsidiaries	148,056	90,988	34,789
Equity in undistributed (loss) earnings of subsidiaries	18,055	(23,167)	65,867
Net income	$ 166,111	$ 67,821	$ 100,656