Note 4 - Loans - Allowance for Credit Losses and Recorded Investment in Financing Receivables (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Dec. 31, 2016
Balance	$ 11,688	$ 11,864	$ 11,544	$ 11,180
Charge-offs	(245)	(357)	(1,051)	(2,398)
Recoveries	249	342	699	3,067
Provision			500
Balance	11,692	11,849	11,692	11,849
Individually evaluated for impairment					$ 918	$ 1,461
Collectively evaluated for impairment					10,774	10,083
Total	11,688	11,864	11,692	11,849	11,692	11,544
Individually evaluated for impairment					14,177	18,794
Collectively evaluated for impairment					810,697	785,417
Total gross loans					824,874	804,211
Commercial Portfolio Segment [Member]
Balance	2,850	2,591	2,849	2,493
Charge-offs			(50)	(1,106)
Recoveries	148	305	383	383
Provision	(354)	(491)	(538)	635
Balance	2,644	2,405	2,644	2,405
Individually evaluated for impairment					453	641
Collectively evaluated for impairment					2,191	2,208
Total	2,850	2,591	2,644	2,405	2,644	2,849
Individually evaluated for impairment					2,980	3,525
Collectively evaluated for impairment					144,232	150,319
Total gross loans					147,212	153,844
Commercial Real Estate Portfolio Segment [Member]
Balance	6,072	6,029	5,578	5,784
Charge-offs				(37)
Recoveries			27	2,481
Provision	232	512	699	(1,687)
Balance	6,304	6,541	6,304	6,541
Individually evaluated for impairment					79	85
Collectively evaluated for impairment					6,225	5,493
Total	6,072	6,029	6,304	6,541	6,304	5,578
Individually evaluated for impairment					1,422	3,125
Collectively evaluated for impairment					530,468	493,617
Total gross loans					531,890	496,742
Residential Portfolio Segment [Member]
Balance	1,197	1,871	1,716	1,577
Charge-offs	(86)	(130)	(370)	(680)
Recoveries	13	18	107	104
Provision	60	45	(269)	803
Balance	1,184	1,804	1,184	1,804
Individually evaluated for impairment					374	721
Collectively evaluated for impairment					810	995
Total	1,197	1,871	1,184	1,804	1,184	1,716
Individually evaluated for impairment					9,738	11,894
Collectively evaluated for impairment					84,602	90,050
Total gross loans					94,340	101,944
Consumer Portfolio Segment [Member]
Balance	1,137	763	955	770
Charge-offs	(159)	(227)	(631)	(575)
Recoveries	88	19	182	99
Provision	134	171	694	432
Balance	1,200	726	1,200	726
Individually evaluated for impairment					12	14
Collectively evaluated for impairment					1,188	941
Total	1,137	763	1,200	726	1,200	955
Individually evaluated for impairment					37	250
Collectively evaluated for impairment					51,395	51,431
Total gross loans					51,432	51,681
Unallocated Financing Receivables [Member]
Balance	432	610	446	556
Charge-offs
Recoveries
Provision	(72)	(237)	(86)	(183)
Balance	360	373	360	373
Individually evaluated for impairment
Collectively evaluated for impairment					360	446
Total	$ 432	$ 610	$ 360	$ 373	360	446
Individually evaluated for impairment
Collectively evaluated for impairment
Total gross loans

Financing receivable allowance for credit losses, provision.

No definition available.

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- Definition

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

+ 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)(1)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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

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- Definition

Amount of valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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

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- Definition

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

+ 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)(4)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

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

+ 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)(3)
-URI http://asc.fasb.org/extlink&oid=84173941&loc=SL6953423-111524

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- Definition

The balance of financing receivables that were collectively evaluated for impairment.

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

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- Definition

The balance of financing receivables that were individually evaluated for impairment.

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

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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82891408&loc=d3e4428-111522

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