Note 2 - Summary of Significant Accounting Policies (Details Textual) $ in Thousands	12 Months Ended
Dec. 31, 2016 USD ($) shares	Dec. 31, 2015 USD ($) shares	Dec. 31, 2014 USD ($)
Number Of Wholly Owned Trusts	1	1
Minimum Risk Rating Range for Loan and Lease Losses	1
Maximum Risk Rating Range for Loan and Lease Losses	8
Percentage of Unallocated Allowance Amount out of Allowance for Loan and Lease Losses	4.00%	5.00%
Percentage of Portfolio Secured by Real Estate	75.00%
Recognize Tax Benefit in Percentage	50.00%
Number of Operating Segments	1
Incentive Plan Granted	100.00%
Share Based Compensation Share Based Awards Non-Qualified Stock Options Exercise Price as Percent of Grant Date Fair Value Minimum	85.00%
Share-based Compensation Share-based Awards Non-Qualified Stock Options Term Maximum	10 years
Share-based Compensation Share-based Awards Non-Qualified Stock Options Exercise Period	5 years
Advertising Expense \| $	$ 171	$ 64	$ 90
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross \| shares	0	20,000
Minimum [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	3 years
Minimum [Member] \| Equipment [Member]
Property, Plant and Equipment, Useful Life	3 years
Maximum [Member] \| Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period	5 years
Maximum [Member] \| Equipment [Member]
Property, Plant and Equipment, Useful Life	7 years
Maximum [Member] \| Building [Member]
Property, Plant and Equipment, Useful Life	39 years

Incentive plan granted.

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Maximum risk rating range for loan and lease losses.

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Minimum risk rating range for loan and lease losses

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Number of wholly-owned trusts held by the entity formed to issue trust preferred securities and related common securities.

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The percentage of a loan portfolio which is secured by Real Estate.

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The percentage of unallocated allowance amount out of allowance for loan and lease losses.

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Recognize tax benefit in percentage.

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Minimum exercise price of non qualified stock options as percent of grant date fair value minimum.

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The maximum term of non-qualified stock options granted during the period.

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The period from the date of the grant of non-qualified stock options which will become exercisable.

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Amount charged to advertising expense for the period, which are expenses incurred with the objective of increasing revenue for a specified brand, product or product line.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 720
-SubTopic 35
-Section 50
-Paragraph 1
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Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Gross number of share options (or share units) granted during the period.

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