Note 5 - Loans - Allowance for Credit Losses and Recorded Investment in Financing Receivables (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Dec. 31, 2016
Balance	$ 11,641	$ 11,495	$ 11,544	$ 11,180
Charge-offs	(359)	(1,734)	(806)	(2,041)
Recoveries	106	2,103	450	2,725
Provision	300		500
Balance	11,688	11,864	11,688	11,864
Individually evaluated for impairment					$ 1,090	$ 1,461
Collectively evaluated for impairment					10,598	10,083
Total	11,641	11,495	11,688	11,864	11,688	11,544
Individually evaluated for impairment					15,820	18,794
Collectively evaluated for impairment					799,568	785,417
Total gross loans					815,388	804,211
Commercial Portfolio Segment [Member]
Balance	2,649	2,466	2,849	2,493
Charge-offs		(1,020)	(51)	(1,106)
Recoveries	36	1,496	235	78
Provision	165	(351)	(183)	1,126
Balance	2,850	2,591	2,850	2,591
Individually evaluated for impairment					602	641
Collectively evaluated for impairment					2,248	2,208
Total	2,649	2,466	2,850	2,591	2,850	2,849
Individually evaluated for impairment					3,113	3,525
Collectively evaluated for impairment					149,091	150,319
Total gross loans					152,204	153,844
Commercial Real Estate Portfolio Segment [Member]
Balance	5,963	5,892	5,578	5,784
Charge-offs		(31)		(37)
Recoveries		475	27	2,480
Provision	109	(307)	467	(2,198)
Balance	6,072	6,029	6,072	6,029
Individually evaluated for impairment					80	85
Collectively evaluated for impairment					5,992	5,493
Total	5,963	5,892	6,072	6,029	6,072	5,578
Individually evaluated for impairment					2,641	3,125
Collectively evaluated for impairment					515,497	493,617
Total gross loans					518,138	496,742
Residential Portfolio Segment [Member]
Balance	1,490	1,961	1,716	1,577
Charge-offs	(115)	(478)	(284)	(550)
Recoveries	19	105	94	86
Provision	(197)	283	(329)	758
Balance	1,197	1,871	1,197	1,871
Individually evaluated for impairment					395	721
Collectively evaluated for impairment					802	995
Total	1,490	1,961	1,197	1,871	1,197	1,716
Individually evaluated for impairment					10,028	11,894
Collectively evaluated for impairment					84,238	90,050
Total gross loans					94,266	101,944
Consumer Portfolio Segment [Member]
Balance	1,074	814	955	770
Charge-offs	(244)	(205)	(471)	(348)
Recoveries	51	27	94	81
Provision	256	127	559	260
Balance	1,137	763	1,137	763
Individually evaluated for impairment					13	14
Collectively evaluated for impairment					1,124	941
Total	1,074	814	1,137	763	1,137	955
Individually evaluated for impairment					38	250
Collectively evaluated for impairment					50,742	51,431
Total gross loans					50,780	51,681
Unallocated Financing Receivables [Member]
Balance	465	362	446	556
Charge-offs
Recoveries
Provision	(33)	248	(14)	54
Balance	432	610	432	610
Individually evaluated for impairment
Collectively evaluated for impairment					432	446
Total	$ 465	$ 362	$ 432	$ 610	432	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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