Note 3 - Loans and Allowance for Loan Losses - Activity in Allowance for Loan Losses and Recorded Investment (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Balance	$ 1,042	$ 1,155	$ 1,063	$ 1,155
Provision for loan losses	31		31
Charge-offs			(21)
Recoveries	13	41	13	41
Balance	1,086	1,196	1,086	1,196
Allowance for loan losses, collectively evaluated for impairment	1,086		1,086		$ 1,063
Loans	93,817		93,817		85,913
Loans; individually evaluated for impairment	2,812		2,812		5,021
Loans; collectively evaluated for impairment	91,005		91,005		80,892
Allowance for loan losses, individually evaluated for impairment
Residential Portfolio Segment [Member]
Balance	578	739	656	648
Provision for loan losses	(33)	27	(99)	118
Charge-offs			(12)
Recoveries
Balance	545	766	545	766
Allowance for loan losses, collectively evaluated for impairment	545		545		656
Loans	43,989		43,989		43,036
Loans; individually evaluated for impairment	1,130		1,130		2,779
Loans; collectively evaluated for impairment	42,859		42,859		40,257
Allowance for loan losses, individually evaluated for impairment
Commercial Real Estate Portfolio Segment [Member]
Balance	365	311	326	383
Provision for loan losses	64	20	112	(52)
Charge-offs			(9)
Recoveries	13		13
Balance	442	331	442	331
Allowance for loan losses, collectively evaluated for impairment	442		442		326
Loans	38,077		38,077		32,175
Loans; individually evaluated for impairment	34		34		533
Loans; collectively evaluated for impairment	38,043		38,043		31,642
Allowance for loan losses, individually evaluated for impairment
Construction and Land Real Estate [Member]
Balance	78	91	72	102
Provision for loan losses	(2)	(44)	4	(55)
Charge-offs
Recoveries		41		41
Balance	76	88	76	88
Allowance for loan losses, collectively evaluated for impairment	76		76		72
Loans	9,669		9,669		9,543
Loans; individually evaluated for impairment	1,648		1,648		1,709
Loans; collectively evaluated for impairment	8,021		8,021		7,834
Allowance for loan losses, individually evaluated for impairment
Commercial Portfolio Segment [Member]
Balance	13	7	4	19
Provision for loan losses	2	(1)	11	(13)
Charge-offs
Recoveries
Balance	15	6	15	6
Allowance for loan losses, collectively evaluated for impairment	15		15		4
Loans	1,428		1,428		383
Loans; individually evaluated for impairment
Loans; collectively evaluated for impairment	1,428		1,428		383
Allowance for loan losses, individually evaluated for impairment
Consumer Portfolio Segment [Member]
Balance	8	7	5	3
Provision for loan losses		(2)	3	2
Charge-offs
Recoveries
Balance	8	$ 5	8	$ 5
Allowance for loan losses, collectively evaluated for impairment	8		8		5
Loans	654		654		776
Loans; individually evaluated for impairment
Loans; collectively evaluated for impairment	654		654		776
Allowance for loan losses, individually evaluated for impairment

Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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

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

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

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Amount of allowance to cover probable credit losses on loans and leases. Includes carryover of or adjustments to the allowance for loan losses in connection with business combinations. Excludes allowance for 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 50
-Paragraph 11B
-Subparagraph (g)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
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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.

+ 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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- Definition

Amount of expense related to estimated loss from loan and lease transactions.

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Reference 1: 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

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