REGULATORY MATTERS - Company's and Bank's Actual Capital Amounts and Ratios (Details) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Consolidated
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Leverage Ratio (tier 1 capital to average assets) Actual Amount	$ 1,437,991	$ 984,620
Tier 1 Leverage Ratio (tier 1 capital to average assets) Actual Ratio	8.476%	9.166%
Tier 1 Leverage Ratio (tier 1 capital to average assets) For Capital Adequacy Purposes Amount	$ 678,650	$ 429,690
Tier 1 Leverage Ratio (tier 1 capital to average assets) For Capital Adequacy Purposes Ratio	4.00%	4.00%
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Actual Amount	$ 1,437,991	$ 895,433
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Actual Ratio	9.925%	10.07%
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Adequacy Purposes Amount	$ 1,014,173	$ 566,859
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Adequacy Purposes Ratio	7.00%	6.375%
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) Actual Amount	$ 1,437,991	$ 984,620
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) Actual Ratio	9.925%	11.073%
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) For Capital Adequacy Purposes Amount	$ 1,231,495	$ 700,237
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) For Capital Adequacy Purposes Ratio	8.50%	7.875%
Total Capital Ratio (total capital to risk weighted assets) Actual Amount	$ 1,874,817	$ 1,087,364
Total Capital Ratio (total capital to risk weighted assets) Actual Ratio	12.94%	12.229%
Total Capital Ratio (total capital to risk weighted assets) For Capital Adequacy Purposes Amount	$ 1,521,259	$ 878,075
Total Capital Ratio (total capital to risk weighted assets) For Capital Adequacy Purposes Ratio	10.50%	9.875%
Ameris Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Leverage Ratio (tier 1 capital to average assets) Actual Amount	$ 1,649,699	$ 1,127,926
Tier 1 Leverage Ratio (tier 1 capital to average assets) Actual Ratio	9.733%	10.506%
Tier 1 Leverage Ratio (tier 1 capital to average assets) For Capital Adequacy Purposes Amount	$ 677,973	$ 429,428
Tier 1 Leverage Ratio (tier 1 capital to average assets) For Capital Adequacy Purposes Ratio	4.00%	4.00%
Tier 1 Leverage Ratio (tier 1 capital to average assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 847,446	$ 536,785
Tier 1 Leverage Ratio (tier 1 capital to average assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	5.00%	5.00%
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Actual Amount	$ 1,649,699	$ 1,127,926
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Actual Ratio	11.394%	12.716%
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Adequacy Purposes Amount	$ 1,013,485	$ 565,486
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Adequacy Purposes Ratio	7.00%	6.375%
CET1 Ratio (common equity tier 1 capital to risk weighted assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 941,094	$ 576,573
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	$ 1,649,699	$ 1,127,926
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) Actual Ratio	11.394%	12.716%
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) For Capital Adequacy Purposes Amount	$ 1,230,661	$ 698,541
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) For Capital Adequacy Purposes Ratio	8.50%	7.875%
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 1,158,269	$ 709,629
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	8.00%	8.00%
Total Capital Ratio (total capital to risk weighted assets) Actual Amount	$ 1,763,965	$ 1,156,745
Total Capital Ratio (total capital to risk weighted assets) Actual Ratio	12.183%	13.041%
Total Capital Ratio (total capital to risk weighted assets) For Capital Adequacy Purposes Amount	$ 1,520,228	$ 875,948
Total Capital Ratio (total capital to risk weighted assets) For Capital Adequacy Purposes Ratio	10.50%	9.875%
Total Capital Ratio (total capital to risk weighted assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 1,447,836	$ 887,036
Total Capital Ratio (total capital to risk weighted assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Ratio	10.00%	10.00%

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

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Common equity tier one risk based capital required for capital adequacy.

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Common equity tier one risk based capital required for capital adequacy to risk weighted assets.

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Common equity tier one risk based capital required to be well capitalized.

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Common Equity Tier 1 capital divided by risk weighted assets as defined by regulations.

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The amount of total capital as defined in the regulations.

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The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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Tier 1 Risk Based Capital as defined in the regulations.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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