Note 3 - Loans (Details) - Loans Modified in a Troubled Debt Restructuring $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)	Sep. 30, 2015 USD ($)	Sep. 30, 2014 USD ($)
Financing Receivable, Modifications [Line Items]
Number of contracts	1	0	2	4
Pre-modification	$ 226	$ 0	$ 1,106	$ 2,221
Post-modification	$ 139	$ 0	$ 1,036	$ 2,225
Real Estate Portfolio Segment [Member] \| Residential [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts	1	0	2	1
Pre-modification	$ 226	$ 0	$ 1,106	$ 49
Post-modification	$ 139	$ 0	$ 1,036	$ 49
Real Estate Portfolio Segment [Member] \| Commercial [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts		0		2
Pre-modification		$ 0		$ 1,771
Post-modification		$ 0		$ 1,775
Real Estate Portfolio Segment [Member] \| Farmland [Member]
Financing Receivable, Modifications [Line Items]
Number of contracts		0		1
Pre-modification		$ 0		$ 401
Post-modification		$ 0		$ 401

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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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