Note 5 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Balance	$ 7,925	$ 8,300	$ 8,297
Charge-offs	(689)	(819)	(1,806)
Recoveries	235	287	159
Provision for (recovery of) loan losses	(81)	157	1,650
Balance	7,390	7,925	8,300
Real Estate Construction Portfolio Segment[Member]
Balance	337	438	576
Charge-offs	0		(29)
Recoveries	0	0	0
Provision for (recovery of) loan losses	61	(101)	(109)
Balance	398	337	438
Consumer Real Estate Portfolio Segment [Member]
Balance	2,027	1,830	1,866
Charge-offs	(38)	(146)	(133)
Recoveries	3	1	2
Provision for (recovery of) loan losses	57	342	95
Balance	2,049	2,027	1,830
Commercial Real Estate Portfolio Segment [Member]
Balance	3,044	3,738	4,109
Charge-offs		(139)	(488)
Recoveries	49	131	83
Provision for (recovery of) loan losses	(295)	(686)	34
Balance	2,798	3,044	3,738
Commercial Non Real Estate Segment [Member]
Balance	1,072	1,063	655
Charge-offs	(107)	(82)	(883)
Recoveries	22	23	10
Provision for (recovery of) loan losses	(385)	68	(1,281)
Balance	602	1,072	1,063
Public Sector and IDA Portfolio Segment[Member]
Balance	419	330	436
Charge-offs	0	0	0
Recoveries	0	0	0
Provision for (recovery of) loan losses	164	89	(106)
Balance	583	419	330
Consumer Non Real Estate Portfolio Segment [Member]
Balance	707	644	627
Charge-offs	(544)	(452)	(273)
Recoveries	161	132	64
Provision for (recovery of) loan losses	426	383	226
Balance	750	707	644
Unallocated Financing Receivables [Member]
Balance	319	257	28
Charge-offs	0	0	0
Recoveries	0	0	0
Provision for (recovery of) loan losses	(109)	62	229
Balance	$ 210	$ 319	$ 257

Amount of recovery of financing receivables doubtful of collection that were previously charged off.

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-Name Accounting Standards Codification
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Amount of direct write-downs of financing receivables charged against the allowance.

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

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