Borrowing capacity available based on pledged collateral.

No definition available.

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Namespace Prefix:	abcb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Federal funds purchased maximum capacity.

+ References

No definition available.

+ Details

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Namespace Prefix:	abcb_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 2
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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

+ Details

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Balance Type:	na
Period Type:	instant

- Definition

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.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 470
-Section 50
-Paragraph 3
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+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Amount of advances or credit lines available from the Federal Home Loan Bank (FHLB).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
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+ Details

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Balance Type:	credit
Period Type:	instant

- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The fair value, as of the date of each statement of financial position presented, of loans which are owned but transferred to serve as collateral for the payment of other debt obligations, and that are reclassified and separately reported in the statement of financial position because the transferee has the right by contract or custom to sell or re-pledge them.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 45
-Paragraph 1
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Balance Type:	debit
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- Details

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- Details

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OTHER BORROWINGS - Narrative (Details) - USD ($)		12 Months Ended
OTHER BORROWINGS - Narrative (Details) - USD ($)	Mar. 15, 2022	Dec. 31, 2018	Mar. 13, 2017
Debt Instrument [Line Items]
Federal home loan bank, advances, general debt obligations, amount of available, unused funds		$ 1,930,000,000
Line of credit facility, remaining borrowing capacity		30,000,000
Credit arrangements for federal funds purchase		117,000,000
Pledged assets separately reported, loans pledged for federal reserve bank, at fair value		1,640,000,000
Loans pledged at federal reserve discount window available for borrowing		$ 1,140,000,000
London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate		3.50%
Senior Subordinated Notes
Debt Instrument [Line Items]
Face amount			$ 75,000,000.0
Interest rate, stated percentage			5.75%
Scenario, Forecast \| Senior Subordinated Notes
Debt Instrument [Line Items]
Redemption price, percentage	100.00%
Scenario, Forecast \| Senior Subordinated Notes \| London Interbank Offered Rate (LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate	3.616%
Advances under revolving credit agreement with a regional bank due September 26, 2020; secured by subsidiary bank stock; variable interest rate at 90-day LIBOR plus 3.50% (6.24% at December 31, 2018)
Debt Instrument [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 100,000,000.0
Basis spread on variable rate		3.50%