Number of shares of equity interests issued or issuable to acquire entity.

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Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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Value of stock issued pursuant to acquisitions during the period.

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Amount of stock repurchase plan authorized.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Number of previously issued common shares repurchased by the issuing entity and held in treasury.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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SHAREHOLDERS' EQUITY - Narrative (Details) - USD ($)		3 Months Ended		9 Months Ended
SHAREHOLDERS' EQUITY - Narrative (Details) - USD ($)	Jul. 01, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Sep. 19, 2019
Subsidiary, Sale of Stock [Line Items]
Repurchase amount		$ 16,000		$ 7,989,000	$ 11,561,000
Increase in shareholders' equity			$ 869,294,000		$ 869,294,000
Fidelity Southern Corporation
Subsidiary, Sale of Stock [Line Items]
Ameris Bancorp common shares issued (in shares)	22,181,522
Share price (in dollars per share)	$ 39.19
Increase in shareholders' equity	$ 869,300,000
Common Stock Repurchase Program, October 2020 Expiration
Subsidiary, Sale of Stock [Line Items]
Authorized repurchase amount						$ 100,000,000.0
Repurchase amount				$ 14,300,000
Number of shares repurchased (in shares)		358,664		358,664