Business combination bargain purchase gain recognized amount net of tax.

No definition available.

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- Definition

Clawback Liability

+ References

No definition available.

+ Details

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- Definition

Fdic Loss Share Reimbursement Percentage Above Threshold

+ References

No definition available.

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- Definition

Fdic Loss Share Reimbursement Percentage Below Threshold

+ References

No definition available.

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- Definition

FDIC loss share threshold.

+ References

No definition available.

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- Definition

Gain on acquisition.

+ References

No definition available.

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- Definition

Loss Sharing Agreement Term

+ References

No definition available.

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- Definition

Number of FDIC assisted banks acquired.

+ References

No definition available.

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- Details

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- Definition

Amount of deferred tax liability attributable to taxable temporary differences due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (c)

-URI http://asc.fasb.org/extlink&oid=39739317&loc=d3e4845-128472

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- Definition

Repayment received or receivable for expenses incurred on behalf of a client or customer, other than those reimbursements received by landlords from tenants.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 225

-SubTopic 10

-Section S99

-Paragraph 2

-Subparagraph (SX 210.5-03.1)

-URI http://asc.fasb.org/extlink&oid=26872669&loc=d3e20235-122688

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 605

-SubTopic 45

-Section 45

-Paragraph 23

-URI http://asc.fasb.org/extlink&oid=21915142&loc=d3e60722-111653

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Assets Acquired in FDIC-Assisted Acquisitions - Additional Information (Detail) (USD $)	12 Months Ended	34 Months Ended	12 Months Ended
	Dec. 31, 2014	Jul. 31, 2012 Acquisition	Dec. 31, 2012	Dec. 31, 2013
Business Acquisition [Line Items]
Number of FDIC-assisted acquisitions participation		10abcb_NumberOfFDICAssistedBanksAcquired
Amount received on loss loss sharing agreement	$ 87,000us-gaap_ReimbursementRevenue
FDIC loss share reimbursement percentage below threshold	80.00%
Clawback liability	6,200,000abcb_ClawbackLiability			5,000,000abcb_ClawbackLiability
SFR and NSF [Member]
Business Acquisition [Line Items]
FDIC loss share reimbursement percentage below threshold	80.00%
FDIC loss share reimbursement percentage above threshold	95.00%
Single Family Residential [Member]
Business Acquisition [Line Items]
FDIC loss share reimbursement percentage below threshold	80.00%
FDIC loss shares threshold	14,500,000
Non Single Family Residential [Member]
Business Acquisition [Line Items]
FDIC loss shares threshold	110,200,000
SFR [Member]
Business Acquisition [Line Items]
loss sharing agreement coverage period	10 years
NSF [Member]
Business Acquisition [Line Items]
loss sharing agreement coverage period	8 years
Reimbursement Limit One [Member] \| Single Family Residential [Member]
Business Acquisition [Line Items]
FDIC loss share reimbursement percentage below threshold	80.00%
FDIC loss shares threshold	8,400,000
Reimbursement Limit One [Member] \| Non Single Family Residential [Member]
Business Acquisition [Line Items]
FDIC loss share reimbursement percentage below threshold	80.00%
FDIC loss shares threshold	123,400,000
Reimbursement Limit Two [Member] \| Single Family Residential [Member]
Business Acquisition [Line Items]
FDIC loss share reimbursement percentage below threshold	30.00%
Reimbursement Limit Two [Member] \| Single Family Residential [Member] \| Minimum [Member]
Business Acquisition [Line Items]
FDIC loss shares threshold	8,400,000
Reimbursement Limit Two [Member] \| Single Family Residential [Member] \| Maximum [Member]
Business Acquisition [Line Items]
FDIC loss shares threshold	11,800,000
Reimbursement Limit Two [Member] \| Non Single Family Residential [Member]
Business Acquisition [Line Items]
FDIC loss share reimbursement percentage below threshold	30.00%
Reimbursement Limit Two [Member] \| Non Single Family Residential [Member] \| Minimum [Member]
Business Acquisition [Line Items]
FDIC loss shares threshold	123,400,000
Reimbursement Limit Two [Member] \| Non Single Family Residential [Member] \| Maximum [Member]
Business Acquisition [Line Items]
FDIC loss shares threshold	181,300,000
Reimbursement Limit Three [Member] \| Single Family Residential [Member]
Business Acquisition [Line Items]
FDIC loss share reimbursement percentage below threshold	80.00%
FDIC loss shares threshold	11,800,000
Reimbursement Limit Three [Member] \| Non Single Family Residential [Member]
Business Acquisition [Line Items]
FDIC loss share reimbursement percentage below threshold	80.00%
FDIC loss shares threshold	181,300,000
Central Bank of Georgia (CBG) [Member]
Business Acquisition [Line Items]
Assets acquisitions			20,000,000
Deferred tax liability recorded with respect to acquisition			7,000,000
After-tax gain on acquisition			13,000,000
American United Bank (AUB) [Member] \| SFR and NSF [Member] \| Minimum [Member]
Business Acquisition [Line Items]
FDIC loss shares threshold	38,000,000
United Security Bank (USB) [Member] \| SFR and NSF [Member] \| Maximum [Member]
Business Acquisition [Line Items]
FDIC loss shares threshold	$ 46,000,000