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Note 4 - Loans and Allowance for Loan Losses - Loans Modified in a Troubled Debt Restructuring (Details) $ in Thousands	3 Months Ended	12 Months Ended
	Mar. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Number of loans	7	7
Pre- modification outstanding principal balance	$ 594	$ 594
Post- modification principal balance	$ 337	$ 365
Real Estate [Member] | Construction, Land Development and Other Land Loans [Member]
Number of loans	1	1
Pre- modification outstanding principal balance	$ 107	$ 107
Post- modification principal balance	$ 80	$ 82
Real Estate [Member] | Secured by 1-4 Family Residential Properties [Member]
Number of loans	3	3
Pre- modification outstanding principal balance	$ 318	$ 318
Post- modification principal balance	$ 141	$ 165
Real Estate [Member] | Secured by Non-farm, Non-residential Properties [Member]
Number of loans	1	1
Pre- modification outstanding principal balance	$ 53	$ 53
Post- modification principal balance	$ 36	$ 37
Commercial and Industrial Loans [Member]
Number of loans	2	2
Pre- modification outstanding principal balance	$ 116	$ 116
Post- modification principal balance	$ 80	$ 81

X

- Definition

Number of financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 33
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953676-111524

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Post-modification amount of investment in financing receivables modified by troubled debt restructurings.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
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+ References

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-Section 50
-Paragraph 33
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