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, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Dec. 31, 2015
Commercial Portfolio Segment [Member]
Balance	$ 2,466	$ 3,245	$ 2,493	$ 3,503
Charge offs	(1,020)	(354)	(1,106)	(406)
Recoveries	1,496	722	78	748
Provision	(351)	(224)	1,126	(456)
Balance	2,591	3,389	2,591	3,389
Individually evaluated for impairment					$ 91	$ 122
Collectively evaluated for impairment					2,500	2,371
Allowance for credit losses	2,466	3,245	2,591	3,389	2,591	2,493
Individually evaluated for impairment					2,909	2,043
Collectively evaluated for impairment					147,501	130,762
Gross loans					150,410	132,805
Commercial Real Estate Portfolio Segment [Member]
Balance	5,892	5,314	5,784	4,875
Charge offs	(31)	(140)	(37)	(139)
Recoveries	475	74	2,480	668
Provision	(307)	199	(2,198)	43
Balance	6,029	5,447	6,029	5,447
Individually evaluated for impairment					92	97
Collectively evaluated for impairment					5,937	5,687
Allowance for credit losses	5,892	5,314	6,029	5,447	6,029	5,784
Individually evaluated for impairment					3,173	7,733
Collectively evaluated for impairment					444,189	420,259
Gross loans					447,362	427,992
Residential Portfolio Segment [Member]
Balance	1,961	1,719	1,577	1,670
Charge offs	(478)	(126)	(550)	(141)
Recoveries	105	7	86	56
Provision	283	(120)	758	(105)
Balance	1,871	1,480	1,871	1,480
Individually evaluated for impairment					708	600
Collectively evaluated for impairment					1,163	977
Allowance for credit losses	1,961	1,719	1,871	1,480	1,871	1,577
Individually evaluated for impairment					12,573	11,582
Collectively evaluated for impairment					89,448	94,387
Gross loans					102,021	105,969
Consumer Portfolio Segment [Member]
Balance	814	572	770	450
Charge offs	(205)	(91)	(348)	(204)
Recoveries	27	14	81
Provision	127	88	260	337
Balance	763	583	763	583
Individually evaluated for impairment					12	13
Collectively evaluated for impairment					751	757
Allowance for credit losses	814	572	763	583	763	770
Individually evaluated for impairment					266	32
Collectively evaluated for impairment					54,081	49,841
Gross loans					54,347	49,873
Unallocated Financing Receivables [Member]
Balance	362	446	556	322
Charge offs
Recoveries
Provision	248	57	54	181
Balance	610	503	610	503
Individually evaluated for impairment
Collectively evaluated for impairment					610	556
Allowance for credit losses	362	446	610	503	610	556
Individually evaluated for impairment
Collectively evaluated for impairment
Gross loans
Balance	11,495	11,296	11,180	10,820
Charge offs	(1,734)	(711)	(2,041)	(890)
Recoveries	2,103	817	2,725	1,472
Provision
Balance	11,864	11,402	11,864	11,402
Individually evaluated for impairment					903	832
Collectively evaluated for impairment					10,961	10,348
Allowance for credit losses	$ 11,495	$ 11,296	$ 11,864	$ 11,402	11,864	11,180
Individually evaluated for impairment					18,921	21,390
Collectively evaluated for impairment					735,219	695,249
Gross loans					$ 754,140	$ 716,639

Financing receivable allowance for credit losses, provision.

No definition available.

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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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=66008989&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=66008989&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=66008989&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=66008989&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=66008989&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=66008989&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=66008989&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=65884687&loc=d3e4428-111522

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