Note 5 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Loans and Allowance for Loan Losses by Evaluation Method (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Allowance for loan losses, individually evaluated for impairment	$ 139	$ 177
Allowance for loan losses, collectively evaluated for impairment	7,251	7,748
Allowance for loan losses	7,390	7,925	$ 8,300	$ 8,297
Loans, individually evaluated for impairment	6,820	11,924
Non-impaired gross loans	703,577	656,758
Loans	710,397	668,682
Real Estate Construction Portfolio Segment[Member]
Allowance for loan losses, individually evaluated for impairment	0
Allowance for loan losses, collectively evaluated for impairment	398	337
Allowance for loan losses	398	337	438	576
Loans, individually evaluated for impairment	0	2,882
Non-impaired gross loans	37,845	31,812
Loans	37,845	34,694
Consumer Real Estate Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment	4	16
Allowance for loan losses, collectively evaluated for impairment	2,045	2,011
Allowance for loan losses	2,049	2,027	1,830	1,866
Loans, individually evaluated for impairment	1,452	1,267
Non-impaired gross loans	174,004	165,698
Loans	175,456	166,965
Commercial Real Estate Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment	0
Allowance for loan losses, collectively evaluated for impairment	2,798	3,044
Allowance for loan losses	2,798	3,044	3,738	4,109
Loans, individually evaluated for impairment	4,340	6,516
Non-impaired gross loans	349,206	333,898
Loans	353,546	340,414
Commercial Non Real Estate Segment [Member]
Allowance for loan losses, individually evaluated for impairment	135	160
Allowance for loan losses, collectively evaluated for impairment	467	912
Allowance for loan losses	602	1,072	1,063	655
Loans, individually evaluated for impairment	1,015	1,229
Non-impaired gross loans	45,520	39,289
Loans	46,535	40,518
Public Sector and IDA Portfolio Segment[Member]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	583	419
Allowance for loan losses	583	419	330	436
Loans, individually evaluated for impairment	0	0
Non-impaired gross loans	60,777	51,443
Loans	60,777	51,443
Consumer Non Real Estate Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment		1
Allowance for loan losses, collectively evaluated for impairment	750	706
Allowance for loan losses	750	707	644	627
Loans, individually evaluated for impairment	13	30
Non-impaired gross loans	36,225	34,618
Loans	36,238	34,648
Unallocated Financing Receivables [Member]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	210	319
Allowance for loan losses	210	319	$ 257	$ 28
Loans, individually evaluated for impairment	0	0
Non-impaired gross loans		0
Loans		$ 0

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

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-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (g)
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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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