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Note 3 - Allowance for Loan Losses, Nonperforming Assets and Impaired Loans - Allowance for Loan Losses (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Balance			$ 7,925	$ 8,300	$ 8,300
Charge-offs			(340)	(552)	(819)
Recoveries			124	101	287
Provision for loan losses	$ 342	$ 464	(130)	523	157
Balance	7,579	8,372	7,579	8,372	7,925
Real Estate Construction Portfolio Segment[Member]
Balance			337	438	438
Charge-offs			0
Recoveries			0	0	0
Provision for loan losses			36	(87)	(101)
Balance	373	351	373	351	337
Consumer Real Estate Portfolio Segment [Member]
Balance			2,027	1,830	1,830
Charge-offs				(138)	(146)
Recoveries			2	1	1
Provision for loan losses			(29)	340	342
Balance	2,000	2,033	2,000	2,033	2,027
Commercial Real Estate Portfolio Segment [Member]
Balance			3,044	3,738	3,738
Charge-offs				(122)	(139)
Recoveries			25	36	131
Provision for loan losses			(78)	116	(686)
Balance	2,991	3,768	2,991	3,768	3,044
Commercial Non Real Estate Segment [Member]
Balance			1,072	1,063	1,063
Charge-offs			(107)	(73)	(82)
Recoveries			10	10	23
Provision for loan losses			(215)	103	68
Balance	760	1,103	760	1,103	1,072
Public Sector and IDA Portfolio Segment[Member]
Balance			419	330	330
Charge-offs			0	0	0
Recoveries			0	0	0
Provision for loan losses			154	83	89
Balance	573	413	573	413	419
Consumer Non Real Estate Portfolio Segment [Member]
Balance			707	644	644
Charge-offs			(233)	(219)	(452)
Recoveries			87	54	132
Provision for loan losses			199	218	383
Balance	760	697	760	697	707
Unallocated Financing Receivables [Member]
Balance			319	257	257
Charge-offs			0	0	0
Recoveries			0	0	0
Provision for loan losses			(197)	(250)	62
Balance	$ 122	$ 7	$ 122	$ 7	$ 319

X

- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(4)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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X

- Definition

Amount of direct write-downs of financing receivables charged against the allowance.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
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X

- Definition

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.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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Amount of expense related to estimated loss from loan and lease transactions.

+ References

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-Publisher FASB
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-Topic 230
-SubTopic 10
-Section 45
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