FAIR VALUE MEASURES - Difference Between Fair Value and Principal Balance of Loans Held for Sale Measured at Fair Value (Details) - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Aggregate fair value of SBA loans held for sale	$ 364,332	$ 281,332
Mortgage loans held for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Aggregate fair value of mortgage loans held for sale	363,002	281,332
Aggregate unpaid principal balance of loans held for sale	355,998	273,915
Past-due loans of 90 days or more	463	781
Nonaccrual loans	463	781
Unpaid principal balance of nonaccrual loans	453	774
SBA loans held for sale
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Aggregate fair value of SBA loans held for sale	1,330	0
Aggregate unpaid principal balance of loans held for sale	$ 1,203	$ 0

Aggregate fair value of loans held for sale.

No definition available.

Name:	abcb_AggregateFairValueOfItemsForWhichFairValueOptionWasElected
Namespace Prefix:	abcb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Aggregate Unpaid Principal Balance Of Items For Which Fair Value Option Was Elected

+ References

No definition available.

+ Details

Name:	abcb_AggregateUnpaidPrincipalBalanceOfItemsForWhichFairValueOptionWasElected
Namespace Prefix:	abcb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair Value, Option, Loans Held as Assets, Unpaid Principal Balance of Nonaccrual Status, Aggregated Difference

+ References

No definition available.

+ Details

Name:	abcb_FairValueOptionLoansHeldAsAssetsUnpaidPrincipalBalanceOfNonaccrualStatusAggregatedDifference
Namespace Prefix:	abcb_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-3

+ Details

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

- Definition

For loans held as assets for which the fair value option has been elected, this item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of those loans that are 90 days or more past due.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (e)(3)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482907/825-10-50-28

+ Details

Name:	us-gaap_FairValueOptionLoansHeldAsAssets90DaysOrMorePastDueAggregateDifference
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

+ References

+ Details

Name:	us-gaap_FairValueOptionLoansHeldAsAssetsAggregateAmountInNonaccrualStatusAggregatedDifference
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Fair value portion of loans held-for-sale including, but not limited to, mortgage loans and finance receivables.

+ References

No definition available.

+ Details

Name:	us-gaap_LoansHeldForSaleFairValueDisclosure
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

Name:	us-gaap_FinancialInstrumentAxis=abcb_MortgageLoansHeldForSaleMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=abcb_SmallBusinessAdminstrationReceivableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: