Note 7 - Loans (Details) - Defaults on Loans with Previous Modifications $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014 USD ($)	Jun. 30, 2015 USD ($)	Jun. 30, 2014 USD ($)
Note 7 - Loans (Details) - Defaults on Loans with Previous Modifications [Line Items]
Troubled debt restructuring defaults, number of contracts	0
Residential Portfolio Segment [Member] | Senior Lien [Member] | Real Estate Loan [Member]
Note 7 - Loans (Details) - Defaults on Loans with Previous Modifications [Line Items]
Troubled debt restructuring defaults, number of contracts		1	2	2
Troubled debt restructuring defaults, recorded investment		$ 83	$ 115	$ 223
Residential Portfolio Segment [Member] | Junior Lien [Member] | Real Estate Loan [Member]
Note 7 - Loans (Details) - Defaults on Loans with Previous Modifications [Line Items]
Troubled debt restructuring defaults, number of contracts		1		1
Troubled debt restructuring defaults, recorded investment		$ 62		$ 62
Commercial Portfolio Segment [Member] | Real Estate Loan [Member]
Note 7 - Loans (Details) - Defaults on Loans with Previous Modifications [Line Items]
Troubled debt restructuring defaults, number of contracts		1	1	1
Troubled debt restructuring defaults, recorded investment		$ 429	$ 407	$ 429
Commercial Portfolio Segment [Member] | Agricultural Loans [Member]
Note 7 - Loans (Details) - Defaults on Loans with Previous Modifications [Line Items]
Troubled debt restructuring defaults, number of contracts		1		1
Troubled debt restructuring defaults, recorded investment		$ 13		$ 13
Commercial Portfolio Segment [Member] | Construction Loans [Member]
Note 7 - Loans (Details) - Defaults on Loans with Previous Modifications [Line Items]
Troubled debt restructuring defaults, number of contracts			1
Troubled debt restructuring defaults, recorded investment			$ 25
Commercial Portfolio Segment [Member] | Loans Secured by Farmland [Member]
Note 7 - Loans (Details) - Defaults on Loans with Previous Modifications [Line Items]
Troubled debt restructuring defaults, number of contracts				4
Troubled debt restructuring defaults, recorded investment				$ 490