Note 6 - Loans (Details) - Loans Modified $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)
Note 6 - Loans (Details) - Loans Modified [Line Items]
Troubled debt restructurings, number of loans	1	4	2	4
Troubled debt restructurings, pre-modification outstanding recorded investment	$ 2,912	$ 3,548	$ 2,964	$ 3,548
Troubled debt restructurings, post-modification outstanding recorded investment	$ 2,912	$ 2,248	$ 2,964	$ 2,248
Term Concessions [Member]
Note 6 - Loans (Details) - Loans Modified [Line Items]
Troubled debt restructurings, number of loans	1	1	2	1
Troubled debt restructurings, pre-modification outstanding recorded investment	$ 2,912	$ 883	$ 2,964	$ 883
Troubled debt restructurings, post-modification outstanding recorded investment	$ 2,912	$ 883	$ 2,964	$ 883
Term and Principal Concessions [Member]
Note 6 - Loans (Details) - Loans Modified [Line Items]
Troubled debt restructurings, number of loans		3		3
Troubled debt restructurings, pre-modification outstanding recorded investment		$ 2,665		$ 2,665
Troubled debt restructurings, post-modification outstanding recorded investment		$ 1,365		$ 1,365
Commercial Portfolio Segment [Member]
Note 6 - Loans (Details) - Loans Modified [Line Items]
Troubled debt restructurings, number of loans	1	1	1	1
Troubled debt restructurings, pre-modification outstanding recorded investment	$ 2,912	$ 883	$ 2,912	$ 883
Troubled debt restructurings, post-modification outstanding recorded investment	$ 2,912	$ 883	$ 2,912	$ 883
Commercial Portfolio Segment [Member] \| Nonfarm Nonresidential [Member]
Note 6 - Loans (Details) - Loans Modified [Line Items]
Troubled debt restructurings, number of loans	1	1	1	1
Troubled debt restructurings, pre-modification outstanding recorded investment	$ 2,912	$ 883	$ 2,912	$ 883
Troubled debt restructurings, post-modification outstanding recorded investment	$ 2,912	$ 883	$ 2,912	$ 883
Single Family ResidentialPortfolioSegment [Member]
Note 6 - Loans (Details) - Loans Modified [Line Items]
Troubled debt restructurings, number of loans			1
Troubled debt restructurings, pre-modification outstanding recorded investment			$ 52
Troubled debt restructurings, post-modification outstanding recorded investment			$ 52
Commercial and Industrial Portfolio Segment[Member]
Note 6 - Loans (Details) - Loans Modified [Line Items]
Troubled debt restructurings, number of loans		3		3
Troubled debt restructurings, pre-modification outstanding recorded investment		$ 2,665		$ 2,665
Troubled debt restructurings, post-modification outstanding recorded investment		$ 1,365		$ 1,365

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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=49124121&loc=SL6953676-111524

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