Note 5 - Loans (Details) - Allowance for Credit Losses and Recorded Investment in Financing Receivables - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2016	Mar. 31, 2015	Mar. 31, 2016	Dec. 31, 2015
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	$ 11,180	$ 10,820
Ending balance	11,495	11,296
ALLL:
Allowance for credit losses: individually evaluated for impairment			$ 1,068	$ 832
Allowance for credit losses: collectively evaluated for impairment			10,427	10,348
Allowance for credit losses	11,180	10,820	11,495	11,180
Gross loans:
Loans, individually evaluated for impairment			19,102	21,390
Loans, collectively evaluated for impairment			705,141	695,249
Gross loans			724,243	716,639
Charge offs	(307)	(179)
Recoveries	622	655
Commercial Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	2,493	3,503
Ending balance	2,466	3,245
ALLL:
Allowance for credit losses: individually evaluated for impairment			124	122
Allowance for credit losses: collectively evaluated for impairment			2,342	2,371
Allowance for credit losses	2,493	3,503	2,466	2,493
Gross loans:
Loans, individually evaluated for impairment			2,603	2,043
Loans, collectively evaluated for impairment			134,118	130,762
Gross loans			136,721	132,805
Charge offs	(85)	(52)
Recoveries	32	26
Provision	26	(232)
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	5,784	4,875
Ending balance	5,892	5,314
ALLL:
Allowance for credit losses: individually evaluated for impairment			94	97
Allowance for credit losses: collectively evaluated for impairment			5,798	5,687
Allowance for credit losses	5,784	4,875	5,892	5,784
Gross loans:
Loans, individually evaluated for impairment			3,555	7,733
Loans, collectively evaluated for impairment			426,323	420,259
Gross loans			429,878	427,992
Charge offs	(6)
Recoveries	528	594
Provision	(414)	(155)
Residential Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	1,577	1,670
Ending balance	1,961	1,719
ALLL:
Allowance for credit losses: individually evaluated for impairment			838	600
Allowance for credit losses: collectively evaluated for impairment			1,123	977
Allowance for credit losses	1,577	1,670	1,961	1,577
Gross loans:
Loans, individually evaluated for impairment			12,913	11,582
Loans, collectively evaluated for impairment			90,745	94,387
Gross loans			103,658	105,969
Charge offs	(73)	(15)
Recoveries	8	35
Provision	449	29
Consumer Portfolio Segment [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	770	450
Ending balance	814	572
ALLL:
Allowance for credit losses: individually evaluated for impairment			12	13
Allowance for credit losses: collectively evaluated for impairment			802	757
Allowance for credit losses	770	450	814	770
Gross loans:
Loans, individually evaluated for impairment			31	32
Loans, collectively evaluated for impairment			53,955	49,841
Gross loans			53,986	49,873
Charge offs	(143)	(112)
Recoveries	54
Provision	133	234
Unallocated Financing Receivables [Member]
Financing Receivable, Allowance for Credit Losses [Line Items]
Beginning balance	556	322
Ending balance	362	446
ALLL:
Allowance for credit losses: collectively evaluated for impairment			362	556
Allowance for credit losses	556	322	$ 362	$ 556
Gross loans:
Provision	$ (194)	$ 124

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Financing receivable allowance for credit losses, provision.

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
-Subparagraph (c)(1)
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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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

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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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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11B
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-URI http://asc.fasb.org/extlink&oid=66008989&loc=SL6953423-111524

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

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

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-Publisher FASB
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-Topic 310
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The balance of financing receivables that were individually evaluated for impairment.

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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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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.

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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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