Atlantic Union Bankshares Corporation Quarterly report pursuant to Section 13 or 15(d)

SECURITIES (Amortized Cost, Gross Unrealized Gains and Losses, and Estimated Fair Values of Investment Securities) (Details) - USD ($) $ in Thousands	Mar. 31, 2018	Dec. 31, 2017
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 1,267,205	$ 971,339
Gross Unrealized Gains	5,984	10,569
Gross Unrealized (Losses)	(20,010)	(7,686)
Estimated Fair Value	1,253,179	974,222
Obligations of States and Political Subdivisions
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	365,816	295,546
Gross Unrealized Gains	3,002	6,842
Gross Unrealized (Losses)	(4,179)	(564)
Estimated Fair Value	364,639	301,824
Corporate and Other Bonds
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	122,903	113,625
Gross Unrealized Gains	1,175	1,131
Gross Unrealized (Losses)	(938)	(876)
Estimated Fair Value	123,140	113,880
Mortgage-Backed Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	767,366	552,431
Gross Unrealized Gains	1,807	2,596
Gross Unrealized (Losses)	(14,761)	(6,169)
Estimated Fair Value	754,412	548,858
Other Securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	11,120	9,737
Gross Unrealized Gains	0	0
Gross Unrealized (Losses)	(132)	(77)
Estimated Fair Value	$ 10,988	$ 9,660