REGULATORY MATTERS - Company's and Bank's Actual Capital Amounts and Ratios (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Consolidated
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Leverage Ratio (tier 1 capital to average assets) Actual Amount	$ 984,620	$ 741,159
Tier 1 Leverage Ratio (tier 1 capital to average assets) Actual Ratio	9.166%	9.713%
Tier 1 Leverage Ratio (tier 1 capital to average assets) For Capital Adequacy Purposes Amount	$ 429,690	$ 305,231
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	$ 895,433	$ 658,529
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Actual Ratio	10.07%	10.291%
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Adequacy Purposes Amount	$ 566,859	$ 367,940
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Adequacy Purposes Ratio	6.375%	5.75%
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) Actual Amount	$ 984,620	$ 741,159
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) Actual Ratio	11.073%	11.582%
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) For Capital Adequacy Purposes Amount	$ 700,237	$ 463,925
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) For Capital Adequacy Purposes Ratio	7.875%	7.25%
Total Capital Ratio (total capital to risk weighted assets) Actual Amount	$ 1,087,364	$ 840,745
Total Capital Ratio (total capital to risk weighted assets) Actual Ratio	12.229%	13.139%
Total Capital Ratio (total capital to risk weighted assets) For Capital Adequacy Purposes Amount	$ 878,075	$ 591,904
Total Capital Ratio (total capital to risk weighted assets) For Capital Adequacy Purposes Ratio	9.875%	9.25%
Ameris Bank
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier 1 Leverage Ratio (tier 1 capital to average assets) Actual Amount	$ 1,127,926	$ 805,238
Tier 1 Leverage Ratio (tier 1 capital to average assets) Actual Ratio	10.506%	10.564%
Tier 1 Leverage Ratio (tier 1 capital to average assets) For Capital Adequacy Purposes Amount	$ 429,428	$ 304,904
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	$ 536,785	$ 381,131
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	$ 1,127,926	$ 805,238
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Actual Ratio	12.716%	12.644%
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Adequacy Purposes Amount	$ 565,486	$ 366,186
CET1 Ratio (common equity tier 1 capital to risk weighted assets) Adequacy Purposes Ratio	6.375%	5.75%
CET1 Ratio (common equity tier 1 capital to risk weighted assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 576,573	$ 413,949
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	$ 1,127,926	$ 805,238
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) Actual Ratio	12.716%	12.644%
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) For Capital Adequacy Purposes Amount	$ 698,541	$ 461,712
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) For Capital Adequacy Purposes Ratio	7.875%	7.25%
Tier 1 Capital Ratio (tier 1 capital to risk weighted assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 709,629	$ 509,476
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	$ 1,156,745	$ 831,029
Total Capital Ratio (total capital to risk weighted assets) Actual Ratio	13.041%	13.049%
Total Capital Ratio (total capital to risk weighted assets) For Capital Adequacy Purposes Amount	$ 875,948	$ 589,081
Total Capital Ratio (total capital to risk weighted assets) For Capital Adequacy Purposes Ratio	9.875%	9.25%
Total Capital Ratio (total capital to risk weighted assets) To Be Well Capitalized Under Prompt Corrective Action Provisions Amount	$ 887,036	$ 636,845
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 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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