Note 5 - Loans (Details) - Loans Modified (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Note 5 - Loans (Details) - Loans Modified [Line Items]
Troubled debt restructurings, number of loans	4	6	16
Troubled debt restructurings, pre-modification outstanding recorded investment	$ 3,548	$ 4,666	$ 7,615
Troubled debt restructurings, post-modification outstanding recorded investment	2,248	4,666	7,610
Construction, Land Development and Other Land Loan [Member]
Note 5 - Loans (Details) - Loans Modified [Line Items]
Troubled debt restructurings, number of loans		1	1
Troubled debt restructurings, pre-modification outstanding recorded investment		60	4,089
Troubled debt restructurings, post-modification outstanding recorded investment		60	4,089
Non Farm Nonresidential [Member]
Note 5 - Loans (Details) - Loans Modified [Line Items]
Troubled debt restructurings, number of loans	1	4	8
Troubled debt restructurings, pre-modification outstanding recorded investment	883	4,364	2,305
Troubled debt restructurings, post-modification outstanding recorded investment	883	4,364	2,305
Commercial Real Estate Loans [Member]
Note 5 - Loans (Details) - Loans Modified [Line Items]
Troubled debt restructurings, number of loans	1	5	9
Troubled debt restructurings, pre-modification outstanding recorded investment	883	4,424	6,394
Troubled debt restructurings, post-modification outstanding recorded investment	883	4,424	6,394
Single Family Real Estate [Member]
Note 5 - Loans (Details) - Loans Modified [Line Items]
Troubled debt restructurings, number of loans			4
Troubled debt restructurings, pre-modification outstanding recorded investment			715
Troubled debt restructurings, post-modification outstanding recorded investment			715
Commercial and Industrial [Member]
Note 5 - Loans (Details) - Loans Modified [Line Items]
Troubled debt restructurings, number of loans	3	1	3
Troubled debt restructurings, pre-modification outstanding recorded investment	2,665	242	506
Troubled debt restructurings, post-modification outstanding recorded investment	1,365	242	501
Rate Concessions [Member]
Note 5 - Loans (Details) - Loans Modified [Line Items]
Troubled debt restructurings, number of loans		1
Troubled debt restructurings, pre-modification outstanding recorded investment		60
Troubled debt restructurings, post-modification outstanding recorded investment		60
Term Concessions [Member]
Note 5 - Loans (Details) - Loans Modified [Line Items]
Troubled debt restructurings, number of loans	1	5	6
Troubled debt restructurings, pre-modification outstanding recorded investment	883	4,606	5,047
Troubled debt restructurings, post-modification outstanding recorded investment	883	4,606	5,047
Term,Term and Principal Concession [Member]
Note 5 - Loans (Details) - Loans Modified [Line Items]
Troubled debt restructurings, number of loans	3
Troubled debt restructurings, pre-modification outstanding recorded investment	2,665
Troubled debt restructurings, post-modification outstanding recorded investment	1,365
Rate and Term Concessions [Member]
Note 5 - Loans (Details) - Loans Modified [Line Items]
Troubled debt restructurings, number of loans			10
Troubled debt restructurings, pre-modification outstanding recorded investment			2,568
Troubled debt restructurings, post-modification outstanding recorded investment			$ 2,563

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

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 33

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953676-111524

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