Note 4 - Loans and Allowance for Loan Losses - Allowance for Loan Losses Activity by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Balance	$ 7,499	$ 7,699
Provision for loan losses	756	145
Loans charged off	(587)	(957)
Recoveries	328	428
Balance	7,996	7,315
Residential Portfolio Segment [Member]
Balance	1,470	939
Provision for loan losses	594	445
Loans charged off	(60)	(73)
Recoveries	55	81
Balance	2,059	1,392
Commercial Real Estate Portfolio Segment [Member]
Balance	2,978	4,315
Provision for loan losses	(581)	(1,087)
Loans charged off	(1)	(559)
Recoveries	27	60
Balance	2,423	2,729
Commercial and Industrial Portfolio Segment [Member]
Balance	1,024	907
Provision for loan losses	316	385
Loans charged off	(4)	(4)
Recoveries	37	72
Balance	1,373	1,360
Consumer Portfolio Segment [Member]
Balance	2,027	1,538
Provision for loan losses	427	402
Loans charged off	(522)	(321)
Recoveries	209	215
Balance	$ 2,141	$ 1,834

A valuation allowance for financing receivables that are expected to be uncollectible.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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- Definition

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

+ References

+ Details

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- Definition

Amount of expense related loan transactions, lease transactions, credit loss from transactions other than loan and lease transactions, and other loss based on assessment of uncollectability from the counterparty to reduce the account to their net realizable value.

+ 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)(2)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=114873765&loc=SL114874048-224260

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

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