2. SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Details Narrative) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Accounting Policies [Abstract]
SBA and Farm Service Agency loans with unpaid balances	$ 233	$ 269
Serviced loans	8,136amrb_ServicedLoans	8,320amrb_ServicedLoans
Proceeds from the sale of other real estate owned	2,283	7,516	3,637
Gain from sale of real estate property	231	44
Recorded investment in other real estate owned	4,647	6,621
Investment in other real estate owned valuation allowances	156	106
Compensation expense, net of related tax benefits	$ 107	$ 84	$ 102
Compensation expense, per diluted share	$ 0.01amrb_EarningsPerShareDiluted1	$ 0.01amrb_EarningsPerShareDiluted1	$ 0.01amrb_EarningsPerShareDiluted1

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The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The net gain (loss) resulting from sales and other disposals of real estate owned for investment purposes.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 225

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-04.14(d))

-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

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-Name Regulation S-X (SX)

-Number 210

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-Paragraph 14

-Subparagraph d

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Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

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-Subparagraph (SX 210.9-03.10(4))

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Valuation adjustments made to other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This excludes real estate assets taken in settlement of troubled loans through surrender or foreclosure.

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The cash inflow associated with the sale of other real estate not otherwise defined in the taxonomy.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

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-Name Accounting Standards Codification

-Glossary Investing Activities

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