REGULATORY MATTERS AND CAPITAL (Schedule of Bank Capital and Ratio) (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier 1 capital to risk weighted assets, actual amount	$ 1,437,908	$ 1,106,871
Common Equity Tier 1 capital to risk weighted assets, actual ratio	10.24%	9.93%
Common Equity Tier 1 capital to risk weighted assets, required for capital adequacy purposes, amount	$ 631,893	$ 501,608
Common Equity Tier 1 capital to risk weighted assets, required for capital adequacy purposes, ratio	4.50%	4.50%
Tier 1 capital to risk weighted assets, actual amount	$ 1,437,908	$ 1,236,709
Tier 1 capital to risk weighted assets, actual ratio	10.24%	11.09%
Tier 1 capital to risk weighted assets, required for capital adequacy purposes, amount	$ 842,524	$ 668,817
Tier 1 capital ratio of risk-weighted assets, required for capital adequacy purposes, ratio	6.00%	6.00%
Total capital to risk weighted assets, actual amount	$ 1,773,835	$ 1,435,711
Total capital to risk weighted assets, actual ratio	12.63%	12.88%
Total capital to risk weighted assets, Required for Capital adequacy purposes, amount	$ 1,123,569	$ 891,753
Total capital to risk weighted assets, required for capital adequacy purposes, ratio	8.00%	8.00%
Tier 1 capital to average adjusted assets, actual amount	$ 1,437,908	$ 1,236,709
Tier 1 capital to average adjusted assets, actual ratio	8.79%	9.71%
Tier 1 capital to average adjusted assets, required for capital adequacy purposes, amount	$ 654,338	$ 509,678
Tier 1 capital to average adjusted assets, required for capital adequacy purposes, ratio	4.00%	4.00%
Atlantic Union Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Common Equity Tier 1 capital to risk weighted assets, actual amount	$ 1,704,426	$ 1,378,039
Common Equity Tier 1 capital to risk weighted assets, actual ratio	12.18%	12.40%
Common Equity Tier 1 capital to risk weighted assets, required for capital adequacy purposes, amount	$ 629,714	$ 500,224
Common Equity Tier 1 capital to risk weighted assets, required for capital adequacy purposes, ratio	4.50%	4.50%
Common Equity Tier 1 capital to risk weighted assets, required in order to be well capitalized under PCA, amount	$ 909,587	$ 722,546
Common Equity Tier 1 capital to risk weighted assets, required in order to be well capitalized under PCA, ratio	6.50%	6.50%
Tier 1 capital to risk weighted assets, actual amount	$ 1,704,426	$ 1,378,039
Tier 1 capital to risk weighted assets, actual ratio	12.18%	12.40%
Tier 1 capital to risk weighted assets, required for capital adequacy purposes, amount	$ 839,619	$ 666,965
Tier 1 capital ratio of risk-weighted assets, required for capital adequacy purposes, ratio	6.00%	6.00%
Tier 1 capital to risk weighted assets, required in order to be well capitalized under PCA, amount	$ 1,119,492	$ 889,287
Tier 1 capital to risk weighted assets, required in order to be well capitalized under PCA, ratio	8.00%	8.00%
Total capital to risk weighted assets, actual amount	$ 1,747,620	$ 1,419,984
Total capital to risk weighted assets, actual ratio	12.48%	12.77%
Total capital to risk weighted assets, Required for Capital adequacy purposes, amount	$ 1,120,269	$ 889,289
Total capital to risk weighted assets, required for capital adequacy purposes, ratio	8.00%	8.00%
Total capital to risk weighted assets, required in order to be well capitalized under PCA, amount	$ 1,400,337	$ 1,111,612
Total capital to risk weighted assets, required in order to be well capitalized under PCA, ratio	10.00%	10.00%
Tier 1 capital to average adjusted assets, actual amount	$ 1,704,426	$ 1,378,039
Tier 1 capital to average adjusted assets, actual ratio	10.45%	10.84%
Tier 1 capital to average adjusted assets, required for capital adequacy purposes, amount	$ 652,412	$ 508,412
Tier 1 capital to average adjusted assets, required for capital adequacy purposes, ratio	4.00%	4.00%
Tier 1 capital to average adjusted assets, required in order to be well capitalized under PCA, amount	$ 815,515	$ 635,515
Tier 1 capital to average adjusted assets, required in order to be well capitalized under PCA, ratio	5.00%	5.00%