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, 2019	Dec. 31, 2018	Jun. 30, 2018	Dec. 31, 2017
Allowance for loan losses, individually evaluated for impairment	$ 129	$ 139
Allowance for loan losses, collectively evaluated for impairment	7,175	7,251
Allowance for loan losses	7,304	7,390	$ 7,579	$ 7,925
Loans, individually evaluated for impairment	6,651	6,820
Loans, collectively evaluated for impairment	723,443	703,577
Loans	730,094	710,397
Real Estate Construction Portfolio Segment[Member]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	516	398
Allowance for loan losses	516	398	373	337
Loans, individually evaluated for impairment
Loans, collectively evaluated for impairment	44,531	37,845
Loans	44,531	37,845
Consumer Real Estate Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment	3	4
Allowance for loan losses, collectively evaluated for impairment	2,063	2,045
Allowance for loan losses	2,066	2,049	2,000	2,027
Loans, individually evaluated for impairment	1,573	1,452
Loans, collectively evaluated for impairment	176,867	174,004
Loans	178,440	175,456
Commercial Real Estate Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment	2
Allowance for loan losses, collectively evaluated for impairment	2,958	2,798
Allowance for loan losses	2,960	2,798	2,991	3,044
Loans, individually evaluated for impairment	4,107	4,340
Loans, collectively evaluated for impairment	364,003	349,206
Loans	368,110	353,546
Commercial Non Real Estate Segment [Member]
Allowance for loan losses, individually evaluated for impairment	124	135
Allowance for loan losses, collectively evaluated for impairment	355	467
Allowance for loan losses	479	602	760	1,072
Loans, individually evaluated for impairment	964	1,015
Loans, collectively evaluated for impairment	43,529	45,520
Loans	44,493	46,535
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	529	583
Allowance for loan losses	529	583	573	419
Loans, individually evaluated for impairment	0	0
Loans, collectively evaluated for impairment	60,854	60,777
Loans	60,854	60,777
Consumer Non Real Estate Portfolio Segment [Member]
Allowance for loan losses, individually evaluated for impairment
Allowance for loan losses, collectively evaluated for impairment	671	750
Allowance for loan losses	671	750	760	707
Loans, individually evaluated for impairment	7	13
Loans, collectively evaluated for impairment	33,659	36,225
Loans	33,666	36,238
Unallocated Financing Receivables [Member]
Allowance for loan losses, individually evaluated for impairment	0	0
Allowance for loan losses, collectively evaluated for impairment	83	210
Allowance for loan losses	83	210	$ 122	$ 319
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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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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