Note 4 - Loans and Allowance for Loan Losses - Allowance for Loan Losses Activity by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Balance	$ 6,952	$ 6,934	$ 7,699	$ 6,648
Provision for loan losses	1,601	1,708	1,921	2,328
Loans charged off	(1,501)	(1,453)	(3,367)	(2,512)
Recoveries	261	348	1,060	1,073
Balance	7,313	7,537	7,313	7,537
Residential Portfolio Segment [Member]
Balance	1,300	906	939	1,087
Provision for loan losses	493	228	870	10
Loans charged off	(445)	(151)	(591)	(322)
Recoveries	83	30	213	238
Balance	1,431	1,013	1,431	1,013
Commercial Real Estate Portfolio Segment [Member]
Balance	2,813	3,464	4,315	1,959
Provision for loan losses	540	802	(636)	2,264
Loans charged off	(434)	(11)	(1,046)	(63)
Recoveries	41	19	327	114
Balance	2,960	4,274	2,960	4,274
Commercial and Industrial Portfolio Segment [Member]
Balance	932	1,416	907	2,589
Provision for loan losses	238	149	588	(1,035)
Loans charged off	(202)	(587)	(605)	(587)
Recoveries	4	1	82	12
Balance	972	979	972	979
Consumer Portfolio Segment [Member]
Balance	1,907	1,148	1,538	1,013
Provision for loan losses	330	529	1,099	1,089
Loans charged off	(420)	(704)	(1,125)	(1,540)
Recoveries	133	298	438	709
Balance	$ 1,950	$ 1,271	$ 1,950	$ 1,271

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

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- 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

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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://www.xbrl.org/2003/role/presentationRef
-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://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 225
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.11)
-URI http://asc.fasb.org/extlink&oid=6879574&loc=d3e536633-122882

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=98514028&loc=d3e3602-108585

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