Note 4 - Loans and the Allowance for Loan Losses - Outstanding Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2016	Jun. 30, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Dec. 31, 2014
Commercial Portfolio Segment [Member] \| Commercial Loans [Member]
Loans	$ 41,942		$ 37,084
Allowance for loan losses	(687)	$ (835)	(639)	$ (558)	$ (628)	$ (574)
Commercial Portfolio Segment [Member] \| Agricultural Loans [Member]
Loans	49,046		39,856
Allowance for loan losses	(471)	(416)	(294)	(261)	(242)	(225)
Commercial Portfolio Segment [Member] \| Real Estate Loan [Member]
Loans	215,166		192,095
Allowance for loan losses	(2,617)	(2,465)	(2,525)	(2,459)	(2,140)	(1,701)
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Loans	18,952		16,188
Allowance for loan losses	(895)	(883)	(874)	(942)	(1,031)	(1,227)
Residential Portfolio Segment [Member] \| Real Estate Loan [Member]
Loans	22,987		25,474
Allowance for loan losses	(298)	(322)	(341)	(333)	(399)	(379)
Residential Portfolio Segment [Member] \| Home Equity Loan [Member]
Loans	41,743		38,327
Consumer Portfolio Segment [Member] \| Automobile Loan [Member]
Loans	53,464		48,365
Allowance for loan losses	(839)	(841)	(784)	(753)	(717)	(581)
Consumer Portfolio Segment [Member] \| Other Loans [Member]
Loans	3,613		3,582
Allowance for loan losses	(93)	(95)	(93)	(72)	(89)	(73)
Loans	446,913		400,971
Deferred loan costs, net	1,963		1,940
Allowance for loan losses	(6,477)	$ (6,430)	(6,078)	$ (5,917)	$ (5,780)	$ (5,451)
	$ 442,399		$ 396,833

Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for loans and leases covered under loss sharing agreements.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements.

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Amount after allowance and deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements and loans held for sale.

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Amount of deferred fees paid by borrowers and unamortized costs incurred to originate loans and leases, unamortized loan commitments and loan syndication fees, and premiums over or discounts from face amounts of loans that are being amortized into income as an adjustment to yield. Excludes amounts for loans and leases covered under loss sharing agreements.

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