Note 19 - Capital Ratios and Regulatory Minimum Requirements (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2014
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Tier 1 leverage capital to average assets	4.00%
Capital required for capital adequacy to risk-weighted assets	8.00%
Tier 1 capital required for capital adequacy to risk-weighted assets	6.00%		4.00%
Consolidated Entities [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Capital	$ 110,352	$ 104,820
Tier 1 capital	102,438	97,320
Common equity tier 1 capital	102,438	97,320
Tier 1 leverage capital	$ 102,438	$ 97,320
Capital to risk-weighted assets	12.52%	12.75%
Tier 1 capital to risk-weighted assets	11.62%	11.84%
Common equity tier 1 capital to risk-weighted assets	11.62%	11.84%
Tier 1 leverage capital to average assets	8.88%	9.16%
Capital required for capital adequacy	$ 70,520	$ 65,777
Tier 1 capital required for capital adequacy	52,890	49,333
Common equity tier 1 capital required for capital adequacy	39,668	36,999
Tier 1 leverage capital required for capital adequacy	$ 46,149	$ 42,479
Capital required for capital adequacy to risk-weighted assets	8.00%	8.00%
Tier 1 capital required for capital adequacy to risk-weighted assets	6.00%	6.00%
Common equity tier 1 capital required for capital adequacy to risk-weighted assets	4.50%	4.50%
Tier 1 leverage capital required for capital adequacy to average assets	4.00%	4.00%
Capital required to be well capitalized	$ 88,150	$ 82,221
Tier 1 capital required to be well capitalized	$ 52,890	$ 49,333
Capital required to be well capitalized to risk-weighted assets	10.00%	10.00%
Tier 1 capital required to be well capitalized to risk-weighted assets	6.00%	6.00%
Bank [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Capital	$ 101,040	$ 96,478
Tier 1 capital	93,126	89,025
Common equity tier 1 capital	93,126	89,025
Tier 1 leverage capital	$ 93,126	$ 89,025
Capital to risk-weighted assets	11.67%	12.10%
Tier 1 capital to risk-weighted assets	10.75%	11.16%
Common equity tier 1 capital to risk-weighted assets	10.75%	11.16%
Tier 1 leverage capital to average assets	8.14%	8.45%
Capital required for capital adequacy	$ 69,277	$ 63,792
Tier 1 capital required for capital adequacy	51,957	47,844
Common equity tier 1 capital required for capital adequacy	38,968	35,883
Tier 1 leverage capital required for capital adequacy	$ 45,761	$ 42,144
Capital required for capital adequacy to risk-weighted assets	8.00%	8.00%
Tier 1 capital required for capital adequacy to risk-weighted assets	6.00%	6.00%
Common equity tier 1 capital required for capital adequacy to risk-weighted assets	4.50%	4.50%
Tier 1 leverage capital required for capital adequacy to average assets	4.00%	4.00%
Capital required to be well capitalized	$ 86,596	$ 79,740
Tier 1 capital required to be well capitalized	69,277	63,792
Common equity tier 1 capital required to be well capitalized	56,287	51,831
Tier 1 leverage capital required to be well capitalized	$ 57,201	$ 52,680
Capital required to be well capitalized to risk-weighted assets	10.00%	10.00%
Tier 1 capital required to be well capitalized to risk-weighted assets	8.00%	8.00%
Common equity tier 1 capital required to be well capitalized to risk-weighted assets	6.50%	6.50%
Tier 1 leverage capital required to be well capitalized to average assets	5.00%	5.00%

Common equity tier 1 capital as defined in the regulations.

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Common equity tier 1 capital to risk-weighted assets as defined in regulations.

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The minimum common equity tier 1 capital (common equity divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of common equity tier 1 capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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The common equity tier 1 capital ratio (common equity tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

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The amount of total capital as defined in the regulations.

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The minimum amount of Total Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Total Capital required to be categorized as well as capitalized under the regulatory framework for prompt corrective action.

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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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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Tier 1 Leverage Capital as defined in the regulations. Also called Core Capital.

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The minimum amount of Tier 1 Leverage Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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The amount of Tier 1 Leverage Capital required to be categorized as well capitalized divided by average assets as defined in the regulatory framework for prompt corrective action.

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Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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Tier 1 Risk Based Capital as defined in the regulations.

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The minimum amount of Tier 1 Risk Based Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The amount of Tier 1 Risk Based Capital required to be categorized as well capitalized under the regulatory framework for prompt corrective action.

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The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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