Note 4 - Loans and the Allowance for Loan Losses - Allocation of the Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended	12 Months Ended
Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Commercial Portfolio Segment [Member] \| Commercial Loans [Member]
Beginning balance	$ 835	$ 628	$ 639	$ 574	$ 574
Charge-offs	(127)	(34)	(200)	(88)
Recoveries	6	12	23	102
Provision	(27)	(48)	225	(30)
Ending balance	687	558	687	558	639
Allowance for loan losses, individually evaluated for impairment	2		2		26
Allowance for loan losses, collectively evaluated for impairment	685		685		613
Loans	41,942		41,942		37,084
Loans, individually evaluated for impairment	16		16		73
Loans, collectively evaluated for impairment	41,926		41,926		37,011
Commercial Portfolio Segment [Member] \| Agricultural Loans [Member]
Beginning balance	416	242	294	225	225
Charge-offs				(3)
Recoveries		6		6
Provision	55	13	177	33
Ending balance	471	261	471	261	294
Allowance for loan losses, individually evaluated for impairment
Allowance for loan losses, collectively evaluated for impairment	471		471		294
Loans	49,046		49,046		39,856
Loans, individually evaluated for impairment	257		257		260
Loans, collectively evaluated for impairment	48,789		48,789		39,596
Commercial Portfolio Segment [Member] \| Real Estate Loan [Member]
Beginning balance	2,465	2,140	2,525	1,701	1,701
Charge-offs			(252)
Recoveries	1		3
Provision	151	319	341	758
Ending balance	2,617	2,459	2,617	2,459	2,525
Allowance for loan losses, individually evaluated for impairment	152		152		371
Allowance for loan losses, collectively evaluated for impairment	2,465		2,465		2,154
Loans	215,166		215,166		192,095
Loans, individually evaluated for impairment	2,588		2,588		3,129
Loans, collectively evaluated for impairment	212,578		212,578		188,966
Commercial Portfolio Segment [Member] \| Construction Loans [Member]
Beginning balance	883	1,031	874	1,227	1,227
Charge-offs	(5)	1	(5)	(54)
Recoveries	30		359
Provision	(13)	(90)	(333)	(231)
Ending balance	895	942	895	942	874
Allowance for loan losses, individually evaluated for impairment	248		248		269
Allowance for loan losses, collectively evaluated for impairment	647		647		605
Loans	18,952		18,952		16,188
Loans, individually evaluated for impairment	913		913		1,029
Loans, collectively evaluated for impairment	18,039		18,039		15,159
Residential Portfolio Segment [Member] \| Real Estate Loan [Member]
Beginning balance	322	399	341	379	379
Charge-offs		(79)		(132)
Recoveries	3	2	39	6
Provision	(27)	11	(82)	80
Ending balance	298	333	298	333	341
Allowance for loan losses, individually evaluated for impairment	53		53		54
Allowance for loan losses, collectively evaluated for impairment	245		245		287
Loans	22,987		22,987		25,474
Loans, individually evaluated for impairment	1,632		1,632		1,593
Loans, collectively evaluated for impairment	21,355		21,355		23,881
Residential Portfolio Segment [Member] \| Equity Lines of Credit [Member]
Beginning balance	573	534	528	691	691
Charge-offs			(23)	(59)
Recoveries	1	1	2	4
Provision	3	4	70	(97)
Ending balance	577	539	577	539	528
Allowance for loan losses, individually evaluated for impairment	25		25		31
Allowance for loan losses, collectively evaluated for impairment	552		552		497
Loans	41,743		41,743		38,327
Loans, individually evaluated for impairment	305		305		311
Loans, collectively evaluated for impairment	41,438		41,438		38,016
Consumer Portfolio Segment [Member] \| Automobile Loan [Member]
Beginning balance	841	717	784	581	581
Charge-offs	(64)	(105)	(222)	(309)
Recoveries	24	29	106	84
Provision	38	112	171	397
Ending balance	839	753	839	753	784
Allowance for loan losses, individually evaluated for impairment
Allowance for loan losses, collectively evaluated for impairment	839		839		784
Loans	53,464		53,464		48,365
Loans, individually evaluated for impairment	121		121		66
Loans, collectively evaluated for impairment	53,343		53,343		48,299
Consumer Portfolio Segment [Member] \| Other Loans [Member]
Beginning balance	95	89	93	73	73
Charge-offs	(31)	(5)	(55)	(27)
Recoveries	9	9	24	36
Provision	20	(21)	31	(10)
Ending balance	93	72	93	72	93
Allowance for loan losses, individually evaluated for impairment
Allowance for loan losses, collectively evaluated for impairment	93		93		93
Loans	3,613		3,613		3,582
Loans, individually evaluated for impairment
Loans, collectively evaluated for impairment	3,613		3,613		3,582
Beginning balance	6,430	5,780	6,078	5,451	5,451
Charge-offs	(227)	(222)	(757)	(672)	(827)
Recoveries	74	59	556	238	354
Provision	200	300	600	900	1,100
Ending balance	6,477	$ 5,917	6,477	$ 5,917	6,078
Allowance for loan losses, individually evaluated for impairment	480		480		751
Allowance for loan losses, collectively evaluated for impairment	5,997		5,997		5,327
Loans	446,913		446,913		400,971
Loans, individually evaluated for impairment	5,832		5,832		6,461
Loans, collectively evaluated for impairment	$ 441,081		$ 441,081		$ 394,510

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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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.

+ References

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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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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of expense related to estimated loss from loan and lease transactions.

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