Note 4 - Allowance for Loan Losses - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Allowance for loan losses, beginning balance	$ 3,758	$ 3,636
Allowance for loan losses, charge- offs	(417)	(1,078)
Allowance for loan losses, recoveries	90	58
Allowance for loan losses, provisions	561	1,142
Allowance for loan losses, ending balance	3,992	3,758
Allowance for loan losses: individually evaluated for impairment
Allowance for loan losses: collectively evaluated for impairment	3,992	3,758
Loans	471,462	444,195
Loans: individually evaluated for impairment	5,082	5,317
Loans: collectively evaluated for impairment	466,380	438,878
Construction Loan Portfolio Segment [Member] \| Residential [Member]
Allowance for loan losses, beginning balance	94	63
Allowance for loan losses, charge- offs
Allowance for loan losses, recoveries
Allowance for loan losses, provisions	17	31
Allowance for loan losses, ending balance	111	94
Allowance for loan losses: individually evaluated for impairment
Allowance for loan losses: collectively evaluated for impairment	111	94
Loans	17,232	15,221
Loans: individually evaluated for impairment
Loans: collectively evaluated for impairment	17,232	15,221
Construction Loan Portfolio Segment [Member] \| Land Acquisition Development And Commercial [Member]
Allowance for loan losses, beginning balance	311	173
Allowance for loan losses, charge- offs		(150)
Allowance for loan losses, recoveries	10
Allowance for loan losses, provisions	(82)	288
Allowance for loan losses, ending balance	239	311
Allowance for loan losses: individually evaluated for impairment
Allowance for loan losses: collectively evaluated for impairment	239	311
Loans	28,903	35,601
Loans: individually evaluated for impairment	43	181
Loans: collectively evaluated for impairment	28,860	35,420
Real Estate Portfolio Segment [Member] \| Residential [Member]
Allowance for loan losses, beginning balance	955	866
Allowance for loan losses, charge- offs	(122)	(293)
Allowance for loan losses, recoveries	30
Allowance for loan losses, provisions	219	382
Allowance for loan losses, ending balance	1,082	955
Allowance for loan losses: individually evaluated for impairment
Allowance for loan losses: collectively evaluated for impairment	1,082	955
Loans	143,385	121,649
Loans: individually evaluated for impairment	538	360
Loans: collectively evaluated for impairment	142,847	121,289
Real Estate Portfolio Segment [Member] \| Commercial [Member]
Allowance for loan losses, beginning balance	1,603	1,516
Allowance for loan losses, charge- offs		(454)
Allowance for loan losses, recoveries	1	43
Allowance for loan losses, provisions	27	498
Allowance for loan losses, ending balance	1,631	1,603
Allowance for loan losses: individually evaluated for impairment
Allowance for loan losses: collectively evaluated for impairment	1,631	1,603
Loans	184,989	173,999
Loans: individually evaluated for impairment	4,228	4,098
Loans: collectively evaluated for impairment	180,761	169,901
Commercial Industrial and Agricultural Portfolio Segment [Member]
Allowance for loan losses, beginning balance	441	461
Allowance for loan losses, charge- offs	(37)	(80)
Allowance for loan losses, recoveries	27
Allowance for loan losses, provisions	25	60
Allowance for loan losses, ending balance	456	441
Allowance for loan losses: individually evaluated for impairment
Allowance for loan losses: collectively evaluated for impairment	456	441
Loans	60,265	61,197
Loans: individually evaluated for impairment	63	379
Loans: collectively evaluated for impairment	60,202	60,818
Equity Lines Portfolio Segment [Member]
Allowance for loan losses, beginning balance	237	338
Allowance for loan losses, charge- offs	(87)
Allowance for loan losses, recoveries
Allowance for loan losses, provisions	102	(101)
Allowance for loan losses, ending balance	252	237
Allowance for loan losses: individually evaluated for impairment
Allowance for loan losses: collectively evaluated for impairment	252	237
Loans	28,969	28,835
Loans: individually evaluated for impairment	210	299
Loans: collectively evaluated for impairment	28,759	28,536
Consumer Portfolio Segment [Member]
Allowance for loan losses, beginning balance	108	97
Allowance for loan losses, charge- offs	(171)	(101)
Allowance for loan losses, recoveries	22	15
Allowance for loan losses, provisions	183	97
Allowance for loan losses, ending balance	142	108
Allowance for loan losses: individually evaluated for impairment
Allowance for loan losses: collectively evaluated for impairment	142	108
Loans	7,719	7,693
Loans: individually evaluated for impairment
Loans: collectively evaluated for impairment	7,719	7,693
Unallocated Financing Receivables [Member]
Allowance for loan losses, beginning balance	9	122
Allowance for loan losses, charge- offs
Allowance for loan losses, recoveries
Allowance for loan losses, provisions	70	(113)
Allowance for loan losses, ending balance	79	9
Allowance for loan losses: individually evaluated for impairment
Allowance for loan losses: collectively evaluated for impairment	79	9
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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