Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Loans and Allowance for Loan Losses by Evaluation Method (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016
Allowance for loan losses, individually evaluated for impairment	$ 162	$ 177
Allowance for loan losses, collectively evaluated for impairment	7,417	7,748
Allowance for loan losses	7,579	7,925	$ 8,372	$ 8,300
Loans, individually evaluated for impairment	12,042	11,924
Loans, collectively evaluated for impairment	679,428	656,758
Loans	691,470	668,682
Real Estate Construction Portfolio Segment[Member]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	373	337
Allowance for loan losses	373	337	351	438
Loans, individually evaluated for impairment	2,618	2,882
Loans, collectively evaluated for impairment	33,605	31,812
Loans	36,223	34,694
Consumer Real Estate Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment	15	16
Allowance for loan losses, collectively evaluated for impairment	1,985	2,011
Allowance for loan losses	2,000	2,027	2,033	1,830
Loans, individually evaluated for impairment	1,135	1,267
Loans, collectively evaluated for impairment	169,113	165,698
Loans	170,248	166,965
Commercial Real Estate Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	2,991	3,044
Allowance for loan losses	2,991	3,044	3,768	3,738
Loans, individually evaluated for impairment	7,092	6,516
Loans, collectively evaluated for impairment	333,490	333,898
Loans	340,582	340,414
Commercial Non Real Estate Segment [Member]
Allowance for loan losses, individually evaluated for impairment	147	160
Allowance for loan losses, collectively evaluated for impairment	613	912
Allowance for loan losses	760	1,072	1,103	1,063
Loans, individually evaluated for impairment	1,175	1,229
Loans, collectively evaluated for impairment	45,326	39,289
Loans	46,501	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	573	419
Allowance for loan losses	573	419	413	330
Loans, individually evaluated for impairment	0	0
Loans, collectively evaluated for impairment	60,010	51,443
Loans	60,010	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	760	706
Allowance for loan losses	760	707	697	644
Loans, individually evaluated for impairment	22	30
Loans, collectively evaluated for impairment	37,884	34,618
Loans	37,906	34,648
Unallocated Financing Receivables [Member]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	122	319
Allowance for loan losses	122	319	$ 7	$ 257
Loans, individually evaluated for impairment	0	0
Loans, collectively evaluated for impairment		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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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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