Note 11 - Capital Ratios and Regulatory Minimum Requirements (Details) - USD ($) $ in Thousands	Jun. 30, 2018	Dec. 31, 2017
Consolidated Entities [Member]
Compliance With Regulatory Capital Requirements Under Banking Regulations [Line Items]
Capital	$ 115,662	$ 110,352
Tier 1 capital	107,397	102,438
Common equity tier 1 capital	107,397	102,438
Tier 1 leverage capital	$ 107,397	$ 102,438
Capital to risk-weighted assets	12.70%	12.52%
Tier 1 capital to risk-weighted assets	11.79%	11.62%
Common equity tier 1 capital to risk-weighted assets	11.79%	11.62%
Tier 1 leverage capital to average assets	9.20%	8.88%
Capital required for capital adequacy	$ 72,861	$ 70,520
Tier 1 capital required for capital adequacy	54,646	52,890
Common equity tier 1 capital required for capital adequacy	40,985	39,668
Tier 1 leverage capital required for capital adequacy	$ 46,655	$ 46,149
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	$ 91,077	$ 88,150
Tier 1 capital required to be well capitalized	$ 54,646	$ 52,890
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	$ 106,129	$ 101,040
Tier 1 capital	97,864	93,126
Common equity tier 1 capital	97,864	93,126
Tier 1 leverage capital	$ 97,864	$ 93,126
Capital to risk-weighted assets	12.03%	11.67%
Tier 1 capital to risk-weighted assets	11.09%	10.75%
Common equity tier 1 capital to risk-weighted assets	11.09%	10.75%
Tier 1 leverage capital to average assets	8.46%	8.14%
Capital required for capital adequacy	$ 70,572	$ 69,277
Tier 1 capital required for capital adequacy	52,929	51,957
Common equity tier 1 capital required for capital adequacy	39,697	38,968
Tier 1 leverage capital required for capital adequacy	$ 46,262	$ 45,761
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	$ 88,215	$ 86,596
Tier 1 capital required to be well capitalized	70,572	69,277
Common equity tier 1 capital required to be well capitalized	57,339	56,287
Tier 1 leverage capital required to be well capitalized	$ 57,827	$ 57,201
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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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 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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