Note 6 - Loans and Allowance for Loan Losses - Carrying Amount of Impaired Loans (Details) - USD ($) $ in Thousands	Mar. 31, 2016	Dec. 31, 2015
Real Estate [Member] \| Construction, Land Development and Other Land Loans [Member]
Impaired loans with no related allowance recorded, Carrying Amount
Impaired loans with no related allowance recorded, Unpaid Principal Balance
Impaired loans with an allowance recorded, Carrying Amount	$ 1,411	$ 1,445
Impaired loans with an allowance recorded, Unpaid Principal Balance	1,411	1,445
Impaired loans with an allowance recorded, Related Allowances	95	95
Total impaired loans, Carrying Amount	1,411	1,445
Total impaired loans, Unpaid Principal Balance	1,411	1,445
Total impaired loans, Related Allowance	95	95
Real Estate [Member] \| Secured by 1-4 Family Residential Properties [Member]
Impaired loans with no related allowance recorded, Carrying Amount	54	54
Impaired loans with no related allowance recorded, Unpaid Principal Balance	54	54
Impaired loans with an allowance recorded, Carrying Amount	197	198
Impaired loans with an allowance recorded, Unpaid Principal Balance	197	198
Impaired loans with an allowance recorded, Related Allowances	5	5
Total impaired loans, Carrying Amount	251	252
Total impaired loans, Unpaid Principal Balance	251	252
Total impaired loans, Related Allowance	$ 5	$ 5
Real Estate [Member] \| Secured by Multi-family Residential Properties [Member]
Impaired loans with no related allowance recorded, Carrying Amount
Impaired loans with no related allowance recorded, Unpaid Principal Balance
Impaired loans with an allowance recorded, Carrying Amount
Impaired loans with an allowance recorded, Unpaid Principal Balance
Impaired loans with an allowance recorded, Related Allowances
Total impaired loans, Carrying Amount
Total impaired loans, Unpaid Principal Balance
Total impaired loans, Related Allowance
Real Estate [Member] \| Secured by Non-farm, Non-residential Properties [Member]
Impaired loans with no related allowance recorded, Carrying Amount
Impaired loans with no related allowance recorded, Unpaid Principal Balance
Impaired loans with an allowance recorded, Carrying Amount	$ 562	$ 573
Impaired loans with an allowance recorded, Unpaid Principal Balance	562	573
Impaired loans with an allowance recorded, Related Allowances	120	130
Total impaired loans, Carrying Amount	562	573
Total impaired loans, Unpaid Principal Balance	562	573
Total impaired loans, Related Allowance	$ 120	$ 130
Commercial and Industrial Loans [Member]
Impaired loans with no related allowance recorded, Carrying Amount
Impaired loans with no related allowance recorded, Unpaid Principal Balance
Impaired loans with an allowance recorded, Carrying Amount	$ 436	$ 444
Impaired loans with an allowance recorded, Unpaid Principal Balance	436	444
Impaired loans with an allowance recorded, Related Allowances	72	80
Total impaired loans, Carrying Amount	436	444
Total impaired loans, Unpaid Principal Balance	436	444
Total impaired loans, Related Allowance	72	80
Impaired loans with no related allowance recorded, Carrying Amount	54	54
Impaired loans with no related allowance recorded, Unpaid Principal Balance	54	54
Impaired loans with an allowance recorded, Carrying Amount	2,606	2,660
Impaired loans with an allowance recorded, Unpaid Principal Balance	2,606	2,660
Impaired loans with an allowance recorded, Related Allowances	292	310
Total impaired loans, Carrying Amount	2,660	2,714
Total impaired loans, Unpaid Principal Balance	2,660	2,714
Total impaired loans, Related Allowance	$ 292	$ 310

Amount of investment of impaired financing receivables with related allowance for credit losses and without a related allowance for credit losses.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 14A
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953550-111524

+ Details

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

- Definition

Amount of allowance for credit losses related to recorded investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Glossary Recorded Investment
-URI http://asc.fasb.org/extlink&oid=65880944

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

+ Details

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Period Type:	instant

- Definition

Amount of unpaid principal balance of impaired financing receivables with related allowance for credit losses and without related allowance for credit losses.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 15
-Subparagraph (a)(4)
-URI http://asc.fasb.org/extlink&oid=66008989&loc=d3e5212-111524

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- Definition

Amount of investment in impaired financing receivables for which there is no related allowance for credit losses.

+ References

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- Definition

Amount of unpaid principal balance of impaired financing receivables for which there is no related allowance for credit losses.

+ References

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- Definition

Amount of investment in impaired financing receivables for which there is a related allowance for credit losses.

+ References

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- Definition

Unpaid principal balance of impaired financing receivables for which there is a related allowance for credit losses.

+ References

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