REGULATORY MATTERS - Company's and Bank's Actual Capital Amounts and Ratios (Details) $ in Thousands	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Consolidated
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Leverage Ratio (tier 1 capital to average assets) Actual Amount	$ 1,701,997	$ 1,437,991
Tier 1 Leverage Ratio (tier 1 capital to average assets) Actual Ratio	0.0899	0.0848
Tier 1 Leverage Ratio (tier 1 capital to average assets) For Capital Adequacy Purposes Amount	$ 757,195	$ 678,650
Tier 1 Leverage Ratio (tier 1 capital to average assets) For Capital Adequacy Purposes Ratio	0.0400	0.0400
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Actual Amount	$ 1,701,997	$ 1,437,991
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Actual Ratio	11.14%	9.93%
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Adequacy Purposes Amount	$ 1,069,425	$ 1,014,173
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Adequacy Purposes Ratio	7.00%	7.00%
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) Actual Amount	$ 1,701,997	$ 1,437,991
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) Actual Ratio	0.1114	0.0993
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) For Capital Adequacy Purposes Amount	$ 1,298,588	$ 1,231,495
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) For Capital Adequacy Purposes Ratio	0.0850	0.0850
Total Capital Ratio (total capital to risk weighted assets) Actual Amount	$ 2,332,385	$ 1,874,817
Total Capital Ratio (total capital to risk weighted assets) Actual Ratio	0.1527	0.1294
Total Capital Ratio (total capital to risk weighted assets) For Capital Adequacy Purposes Amount	$ 1,604,138	$ 1,521,259
Total Capital Ratio (total capital to risk weighted assets) For Capital Adequacy Purposes Ratio	0.1050	0.1050
Ameris Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Leverage Ratio (tier 1 capital to average assets) Actual Amount	$ 1,964,717	$ 1,649,699
Tier 1 Leverage Ratio (tier 1 capital to average assets) Actual Ratio	0.1039	0.0973
Tier 1 Leverage Ratio (tier 1 capital to average assets) For Capital Adequacy Purposes Amount	$ 756,510	$ 677,973
Tier 1 Leverage Ratio (tier 1 capital to average assets) For Capital Adequacy Purposes Ratio	0.0400	0.0400
Tier 1 Leverage Ratio (tier 1 capital to average assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 945,637	$ 847,446
Tier 1 Leverage Ratio (tier 1 capital to average assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	0.0500	0.0500
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Actual Amount	$ 1,964,717	$ 1,649,699
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Actual Ratio	12.87%	11.39%
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Adequacy Purposes Amount	$ 1,068,756	$ 1,013,485
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Adequacy Purposes Ratio	7.00%	7.00%
CET1 Ratio (common equity tier 1 capital to risk weighted assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 992,417	$ 941,094
CET1 Ratio (common equity tier 1 capital to risk weighted assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	6.50%	6.50%
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) Actual Amount	$ 1,964,717	$ 1,649,699
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) Actual Ratio	0.1287	0.1139
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) For Capital Adequacy Purposes Amount	$ 1,297,775	$ 1,230,661
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) For Capital Adequacy Purposes Ratio	0.0850	0.0850
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 1,221,436	$ 1,158,269
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	0.0800	0.0800
Total Capital Ratio (total capital to risk weighted assets) Actual Amount	$ 2,165,760	$ 1,763,965
Total Capital Ratio (total capital to risk weighted assets) Actual Ratio	0.1419	0.1218
Total Capital Ratio (total capital to risk weighted assets) For Capital Adequacy Purposes Amount	$ 1,603,134	$ 1,520,228
Total Capital Ratio (total capital to risk weighted assets) For Capital Adequacy Purposes Ratio	0.1050	0.1050
Total Capital Ratio (total capital to risk weighted assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 1,526,795	$ 1,447,836
Total Capital Ratio (total capital to risk weighted assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	0.1000	0.1000

Common Equity Tier 1 Risk Based Capital as defined in the regulations.

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