Note 4 - Allowance for Loan Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Allowance for loan losses, beginning balance	$ 3,298	$ 3,332
Allowance for loan losses, charge- offs	(848)	(80)
Allowance for loan losses, recoveries	104	46
Allowance for loan losses, provisions	1,082
Allowance for loan losses, ending balance	3,636	3,298
Allowance for loan losses: individually evaluated for impairment	17	17
Allowance for loan losses: collectively evaluated for impairment	3,619	3,281
Loans	418,991	367,358
Loans: individually evaluated for impairment	7,276	7,837
Loans: collectively evaluated for impairment	411,715	359,521
Construction Loan Portfolio Segment [Member] \| Residential [Member]
Allowance for loan losses, beginning balance	83	43
Allowance for loan losses, charge- offs
Allowance for loan losses, recoveries
Allowance for loan losses, provisions	(20)	40
Allowance for loan losses, ending balance	63	83
Allowance for loan losses: individually evaluated for impairment
Allowance for loan losses: collectively evaluated for impairment	63	83
Loans	10,204	11,779
Loans: individually evaluated for impairment
Loans: collectively evaluated for impairment	10,204	11,779
Construction Loan Portfolio Segment [Member] \| Land Acquisition Development And Commercial [Member]
Allowance for loan losses, beginning balance	187	453
Allowance for loan losses, charge- offs	(2)
Allowance for loan losses, recoveries
Allowance for loan losses, provisions	(12)	(266)
Allowance for loan losses, ending balance	173	187
Allowance for loan losses: individually evaluated for impairment
Allowance for loan losses: collectively evaluated for impairment	173	187
Loans	27,480	27,440
Loans: individually evaluated for impairment
Loans: collectively evaluated for impairment	27,480	27,440
Real Estate Portfolio Segment [Member] \| Residential [Member]
Allowance for loan losses, beginning balance	1,047	833
Allowance for loan losses, charge- offs	(4)
Allowance for loan losses, recoveries	45	1
Allowance for loan losses, provisions	(222)	213
Allowance for loan losses, ending balance	866	1,047
Allowance for loan losses: individually evaluated for impairment
Allowance for loan losses: collectively evaluated for impairment	866	1,047
Loans	111,626	100,268
Loans: individually evaluated for impairment	770	247
Loans: collectively evaluated for impairment	110,856	100,021
Real Estate Portfolio Segment [Member] \| Commercial [Member]
Allowance for loan losses, beginning balance	1,001	1,012
Allowance for loan losses, charge- offs	(606)
Allowance for loan losses, recoveries
Allowance for loan losses, provisions	1,121	(11)
Allowance for loan losses, ending balance	1,516	1,001
Allowance for loan losses: individually evaluated for impairment	17	17
Allowance for loan losses: collectively evaluated for impairment	1,499	984
Loans	172,248	140,952
Loans: individually evaluated for impairment	6,495	7,578
Loans: collectively evaluated for impairment	165,753	133,374
Commercial Industrial and Agricultural Portfolio Segment [Member]
Allowance for loan losses, beginning balance	531	319
Allowance for loan losses, charge- offs	(34)
Allowance for loan losses, recoveries		10
Allowance for loan losses, provisions	(36)	202
Allowance for loan losses, ending balance	461	531
Allowance for loan losses: individually evaluated for impairment
Allowance for loan losses: collectively evaluated for impairment	461	531
Loans	59,809	53,012
Loans: individually evaluated for impairment	11	12
Loans: collectively evaluated for impairment	59,798	53,000
Equity Lines Portfolio Segment [Member]
Allowance for loan losses, beginning balance	277	423
Allowance for loan losses, charge- offs	(99)
Allowance for loan losses, recoveries	10	1
Allowance for loan losses, provisions	150	(147)
Allowance for loan losses, ending balance	338	277
Allowance for loan losses: individually evaluated for impairment
Allowance for loan losses: collectively evaluated for impairment	338	277
Loans	29,956	26,376
Loans: individually evaluated for impairment
Loans: collectively evaluated for impairment	29,956	26,376
Consumer Portfolio Segment [Member]
Allowance for loan losses, beginning balance	85	65
Allowance for loan losses, charge- offs	(103)	(80)
Allowance for loan losses, recoveries	49	34
Allowance for loan losses, provisions	66	66
Allowance for loan losses, ending balance	97	85
Allowance for loan losses: individually evaluated for impairment
Allowance for loan losses: collectively evaluated for impairment	97	85
Loans	7,668	7,531
Loans: individually evaluated for impairment
Loans: collectively evaluated for impairment	7,668	7,531
Unallocated Financing Receivables [Member]
Allowance for loan losses, beginning balance	87	184
Allowance for loan losses, charge- offs
Allowance for loan losses, recoveries
Allowance for loan losses, provisions	35	(97)
Allowance for loan losses, ending balance	122	87
Allowance for loan losses: individually evaluated for impairment
Allowance for loan losses: collectively evaluated for impairment	122	87
Loans
Loans: individually evaluated for impairment
Loans: collectively evaluated for impairment

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.

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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 of expense related to estimated loss from loan and lease transactions.

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